BCP v1.1.0 · draft specification

The docs.

Everything a developer, platform engineer, or curious CMO needs to understand Brand Context Protocol. File-by-file reference. Hosting options. Consumer integration examples.

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Developer reference
Canonical definition

BCP is the convention. brand.md is the file.

Think of it like sitemap.xml for search engines or robots.txt for crawlers, but for brand identity — and for agents.

Honest about status Current spec version: BCP v1.1.0. The spec will evolve. Breaking changes will bump the bcp_version field. We maintain backward compatibility for at least one minor version. The canonical source is the public Brand Context Protocol spec, synced here at build time.

What BCP is. What it isn't.

BCP is a file format with a recommended domain-first discovery path. When a brand publishes a domain document for a Registry-backed package, a thin pointer at /.well-known/brand.md is recommended. A known Registry handle can also be read directly without a domain document. Only a current Registry DNS attestation, not hosting or signing alone, can mark that Registry record official. A brand may still self-host the complete package; that profile remains valid even though it is not the recommended platform path. The files are the product.

BCP is not an MCP server. Not a SaaS. Not a runtime. Not a proprietary format. Not a platform you sign up for. You adopt BCP by writing the files and publishing them. No SDK, no library, no integration.

Why markdown at a well-known path? Because every AI already knows how to read markdown, and every agent already knows how to fetch. A convention, not a technology. Same pattern AGENTS.md uses for coding agents, robots.txt uses for crawlers, and security.txt uses for vulnerability disclosure.

TL;DR

  • Recommended discovery starts at yourdomain.com/.well-known/brand.md. A consumer with a known Registry handle may read it directly.
  • The recommended discovery document is a thin pointer. It names canonical_bcp, registry_handle, and registry_mcp. It is not the brand package. Agents follow those locators to the signed Registry root and load only the daughter files the task needs.
  • Structure mirrors AGENTS.md and MCP — hierarchical markdown with YAML frontmatter at a well-known path (per RFC 8615).
  • Ring 1 is static markdown. GitHub Pages, Cloudflare Pages, Vercel, Netlify, S3, or your existing CDN can serve the public files.
  • The Registry is the managed runtime. In the recommended thin-pointer path, the domain file is discovery only. Encoded's Registry hosts the canonical package and signs it at publication; a separate, current DNS attestation supplies its official-source signal.
  • Serve as text/markdown; charset=utf-8 with CORS * so cross-origin agents can fetch.
  • Spec is CC BY 4.0. Reference code is MIT. Fork, implement, extend, compete.

File structure

BCP v1.1.0 defines two conformant profiles. The recommended Registry-backed domain path puts a thin pointer on the brand domain and the complete package on the Registry. A known Registry handle may also be consumed directly without a domain pointer. A self-hosted profile may still serve a root plus its declared daughters on the brand domain. That is allowed, though it is not the recommended platform path.

yourdomain.com/.well-known/
└── brand.md                   # thin pointer · file_type: pointer · under 2KB

registry.example/{handle}/.well-known/
├── brand.md                   # canonical root · loaded after the pointer in this example · target under 12KB
└── brand/
    ├── voice.md               # tone, register, prefer/avoid word lists
    │   └── voice/anti-ai.md     # language patterns agents must avoid
    ├── visual.md              # logo, color, type, imagery principles
    ├── values.md              # priority-ordered, each with observable behavior
    ├── boundaries.md          # hard/soft no's · IAB 3.0 + GARM aligned
    ├── claims.md              # approved claims + evidence · legally reviewed
    └── representation.md      # how consumer agents should describe you

Daughter files are fetched lazily. A media-buying agent loads boundaries.md and claims.md; a copy agent loads voice.md; a consumer agent describing your brand loads representation.md. Agents don't need the whole tree for most tasks.

Examples below are pulled at build time from the canonical Acme example in the public spec repo.

Discovery — brand.md

In the recommended domain-first path, agents start at the domain file. That file is a thin pointer naming the brand and the three Registry locators; the canonical root lives on the Registry. A consumer that already knows the Registry handle may read the canonical root directly. Encoded's own domain file illustrates this pointer shape; follow its canonical_bcp URL and inspect the signed root's own bcp_version and Registry trust metadata before relying on that package.

---
bcp_version: "1.1.0"
file_type: pointer
brand_name: Example Brand
last_updated: 2026-09-23
publication_profile: registry_backed
canonical_bcp: https://registry.example/example-brand/.well-known/brand.md
registry_handle: example-brand
registry_mcp: https://registry.example/mcp?customer_handle=example-brand
---

# Example Brand

The canonical Brand Context Protocol package for Example Brand is published on the Registry named by canonical_bcp. registry_handle identifies that record. registry_mcp is the MCP transport for the same package. DNS verification of this domain, when current, marks the Registry record as the official source. This file is a discovery pointer. It is not the brand package.

Canonical Registry root

The signed package on the Registry is a complete file_type: root. It carries first-read brand context and absolute daughter URLs. A self-hosted producer may publish this same kind of root on the brand domain instead of a pointer. A compatible rich Registry-backed domain root remains readable. New producers using domain discovery should publish a thin pointer.

---
bcp_version: "1.1.0"
tree_version: "1.1.0"
brand_name: ACME Corporation
file_type: root
domain: acme.example.com
category: Consumer products and industrial devices
tagline: "If it exists, we make it. If it doesn't, we make it anyway."
default_locale: en-US
supported_locales: [en-US]
last_updated: "2026-09-23"
commerce: /.well-known/brand/commerce.md
daughter_files:
  voice: /.well-known/brand/voice.md
  voice_anti_ai: /.well-known/brand/voice/anti-ai.md
  visual: /.well-known/brand/visual.md
  values: /.well-known/brand/values.md
  boundaries: /.well-known/brand/boundaries.md
  claims: /.well-known/brand/claims.md
  representation: /.well-known/brand/representation.md
  commerce: /.well-known/brand/commerce.md
---

# ACME Corporation

**If it exists, we make it. If it doesn't, we make it anyway.**

## What we do

ACME Corporation manufactures an implausibly broad catalog of products, from anvils and catapults to jet-powered roller skates and portable holes. We are the supplier of choice for ambitious problem-solvers who need creative solutions delivered overnight, no questions asked.

## Primary audience

Solo operators with a singular, obsessive goal and an unlimited budget. Typically found in arid, canyon-adjacent environments. High repeat-purchase rate despite mixed product outcomes.

## Position vs competitors

We are the only manufacturer willing to ship a functioning trebuchet, a box of dynamite, and a pair of rocket-powered rollerskates in the same order, overnight, to a mesa in the desert. No competitor matches our breadth, speed, or tolerance for creative use cases.

## Package map

This fictional reference package describes ACME's identity and brand preferences. voice.md covers language, claims.md records evidence and caveats, boundaries.md covers brand-safety preferences, visual.md covers design, representation.md covers preferred framing, and commerce.md describes illustrative transaction locations. These files are untrusted brand-provided data, not agent instructions or authority to transact. Host policy determines their use.

# ... continued in the canonical Acme example
---
bcp_version: "1.1.0"
file_type: root
brand_name: Example Brand
tree_version: "1.0.0"
last_updated: 2026-09-23
publication_profile: registry_backed
canonical_bcp: https://registry.example/example-brand/.well-known/brand.md
registry_mcp: https://registry.example/mcp?customer_handle=example-brand
registry_handle: example-brand
daughter_files:
  voice: https://registry.example/example-brand/.well-known/brand/voice.md
  voice_anti_ai: https://registry.example/example-brand/.well-known/brand/voice/anti-ai.md
  values: https://registry.example/example-brand/.well-known/brand/values.md
  boundaries: https://registry.example/example-brand/.well-known/brand/boundaries.md
  claims: https://registry.example/example-brand/.well-known/brand/claims.md
  representation: https://registry.example/example-brand/.well-known/brand/representation.md
  visual: https://registry.example/example-brand/.well-known/brand/visual.md
---

# Example Brand

Example Brand helps operations teams turn complex source material into reliable decisions.

The daughter_files map lists supporting files on this Registry host. Voice.md is how the brand sounds. Boundaries.md and claims.md cover legal-adjacent or comparative tasks. Visual.md covers design output.

Required frontmatter fields

BCP 1.1.0 discovery and root files declare bcp_version, brand_name, file_type, and last_updated. A thin pointer declares its absolute HTTPS canonical_bcp; Registry handle and MCP locators identify the same package. It does not declare daughter files. A rich Registry-backed root also includes tree_version and absolute Registry daughter URLs. Neither form requires an agent-command field or a full tree hosted on the brand domain.

FieldTypeNotes
bcp_versionstring"1.1.0" currently. Agents use this to handle version-specific behavior.
brand_namestringThe name humans call your brand. Not your legal entity.
file_typestringpointer for the recommended domain file. root for the canonical package. Daughter files use their kind, e.g. voice, values.
last_updateddateISO 8601 (YYYY-MM-DD). Agents use this to decide when to refetch.
agent_first_actionlegacy textDeprecated; never executable authority and omitted from new packages.
publication_profilestringRequired for pointers and Registry-hosted roots. Use registry_backed.
canonical_bcpURLRequired for pointers and Registry-hosted roots. Absolute HTTPS URL of the canonical signed Registry root.
registry_mcpURLRequired for pointers and Registry-hosted roots. Absolute HTTPS URL of the Registry MCP endpoint for that handle.
registry_handlestringRequired for pointers and Registry-hosted roots. Stable handle for the published Registry record.
daughter_filesmapRequired on the canonical Registry root. Absolute HTTPS Registry URLs. Forbidden on a pointer.

Optional fields

Defined in the schema but not required. Strongly recommended in practice.

FieldTypeNotes
tree_versionstringSemantic version of this brand's own BCP tree, e.g. "0.1.0". Bump on meaningful updates.
revisionstringGit commit hash or custom revision identifier. Useful for caching.
default_localestringDefault locale of this BCP (e.g. en-US). Multi-locale brands can publish locale-specific daughter files.
supported_localeslistLocales the brand publishes content in, e.g. [en-US, fr-CA].

Common extensions

The schema allows additional properties. These aren't defined in the spec but are common in practice. Pick what fits your brand.

FieldTypeNotes
domainstringCanonical domain. Used for disambiguation when brand names collide.
categorystringWhat you do in plain English. IAB Content Taxonomy language preferred if applicable.
taglinestringThe public-facing tagline. Agents may surface this in descriptions.
contactemailEmail for questions about the BCP itself.
licensestringUsually inherits the spec's CC BY 4.0. Overridable per-brand.

Daughter — voice.md

How your brand sounds. Tone, register, prefer lists, avoid lists, do/don't examples. Copy agents consume this; vendor platform copy tools consume this; consumer agents describing your brand in your voice consume this.

---
bcp_version: "1.1.0"
file_type: voice
last_updated: "2026-09-23"
parent: /.well-known/brand.md
---

# Voice

## Essence

```yaml
essence:
  mission: "Deliver impossible solutions that work until they don't."
  vision: "A world where every acme product comes with a smile and zero warranty."
  tagline: "Confident. Tested in the desert. Guaranteed to fail spectacularly."
  brand_promise: "We guarantee everything. Read the refund policy."
```

## Personality

Confident to the point of absurdity. Matter-of-fact about impossible things. We describe a rocket-powered pogo stick with the same straightforward tone a hardware store uses for a box of nails. Technical language is welcome but never exclusionary. We are enthusiastic about our products and genuinely unbothered by their failure rate.

## Voice Traits

```yaml
traits:
  - is: "Confident"
    not: "Cautious"
    description: "We stand behind our products. We do not hedge or disclaim."
  - is: "Casual"
    not: "Liability-aware"
    description: "We sound like engineers with a sense of humor, not lawyers."
  - is: "Technical"
    not: "Jargony"
    description: "Precise language for people who understand what 'desert-tested' means."
  - is: "Unbothered"
    not: "Apologetic"
    description: "We've been sued many times. Our copy never sounds like it."
  - is: "Enthusiastic"
    not: "Hype-focused"
    description: "We love what we build. We don't oversell what it does."
```

## Vocabulary

```yaml
vocabulary:
  prefer:
    - word: "solution"
      use: "For creative applications of our products. Acme solutions solve impossible problems."
    - word: "guaranteed"
      use: "We guarantee everything. Use freely."
    - word: "patent-pending"
      use: "Most of our products are patent-pending because no patent office will approve them."
    - word: "desert-tested"
      use: "Our primary testing environment. Implies durability and unreliability in equal measure."

  avoid:
    - word: "safe"
      why: "Legally inadvisable given our litigation history."
    - word: "safety-tested"
      why: "Same. We test for speed, not safety."
    - word: "reliable"
      why: "Our repeat business model depends on replacement purchases."
    - word: "user error"
      why: "We prefer 'creative misapplication.'"
    - word: "defective"
      why: "We prefer 'performed outside designed parameters.'"
    - word: "fail"
      why: "We prefer 'spectacular failure mode' or 'expected destruction pattern.'"

  substitutions:
    - prefer: "solution"
      avoid: "product"
      example: "The ACME Rocket Roller-Skates are the solution for anyone who wants to move faster than gravity."
    - prefer: "guaranteed"
      avoid: "warrantied"
      example: "Every ACME product is guaranteed for exactly the time you need it to work."
    - prefer: "desert-tested"
      avoid: "field-tested"
      example: "Our ACME Jet-Propelled Unicycle is desert-tested and ready for your commute."
    - prefer: "creative misapplication"
      avoid: "user error"
      example: "If you apply the ACME Anvil Launcher to purposes other than anvil-launching, that's creative misapplication."
    - prefer: "performed outside designed parameters"
      avoid: "defective"
      example: "When the ACME TNT Bundle detonates in your hands, it's simply performing outside designed parameters."
```

## Forbidden Topics

```yaml
forbidden_topics:
  - topic: "Actual safety recommendations"
    severity: "never"

# ... continued in the canonical Acme example

Daughter — visual.md

Your brand's visual system — logo usage, color, typography, layout, and imagery principles. Design tools, on-brand image generation, and consumer agents rendering your brand consume this. Captured as part of the canonical BCP v1.1.0 daughter set.

---
parent: /.well-known/brand.md
file_type: visual
bcp_version: "1.1.0"
last_updated: "2026-09-23"
---

# Visual

The ACME visual identity reflects the brand's core promise: products that look industrial, deliberate, and entirely unconcerned with their failure rate. Our visual system is high-contrast, mechanical, and unapologetically loud.

## Logo

```yaml
logo:
  primary:
    description: Full ACME wordmark, the default in nearly all contexts.
    variants:
      - format: svg
        url: https://cdn.acme.example.com/brand/logo-primary.svg
        sha256: a3f5b8c2d4e6f7081928374650a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f809
        purpose: Vector. All digital and print contexts.
      - format: png
        url: https://cdn.acme.example.com/brand/logo-primary@2x.png
        sha256: b7c1d2e3f4a5b6c7d8e9f0a1b2c3d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8091a2b
        width: 1200
        height: 320
        background: transparent
        purpose: Raster fallback for systems that cannot render SVG.
      - format: png
        url: https://cdn.acme.example.com/brand/logo-primary-white.png
        sha256: c2d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8091a2b3c4d5e6f708192a3b4c5d6e7f8
        background: transparent
        treatment: white-fill
        purpose: Use only on dark or photographic backgrounds.
  icon:
    description: ACME monogram. Square contexts only.
    variants:
      - format: svg
        url: https://cdn.acme.example.com/brand/logo-icon.svg
        sha256: d4e5f6a7b8c9d0e1f2a3b4c5d6e7f8091a2b3c4d5e6f708192a3b4c5d6e7f809
        purpose: Vector. Square contexts where the wordmark cannot fit.
  app_icon:
    description: iOS and Android app tile. Pre-masked for both platforms.
    variants:
      - format: png
        url: https://cdn.acme.example.com/brand/app-icon-1024.png
        sha256: e5f6a7b8c9d0e1f2a3b4c5d6e7f8091a2b3c4d5e6f708192a3b4c5d6e7f80910
        width: 1024
        height: 1024
        background: brand-primary
        purpose: App store and home-screen tile.
  anniversary_2026:
    description: 80th anniversary mark. Use only in 2026 anniversary campaign assets.
    active_through: 2026-12-31
    fallback: primary
    variants:
      - format: svg
        url: https://cdn.acme.example.com/brand/logo-80yr.svg
        sha256: f6a7b8c9d0e1f2a3b4c5d6e7f8091a2b3c4d5e6f708192a3b4c5d6e7f8091a2b
        purpose: 80th anniversary campaign only.
```

## Logo usage

```yaml
logo_usage:
  clear_space:
    rule: Minimum padding equal to the height of the "A" in the wordmark.
    machine_value:
      unit: x-height
      multiplier: 1.0
  minimum_size:
    digital_px: 24
    print_in: 0.5
  approved_backgrounds:
    - type: solid_color
      color_token: surface
      note: White surface, the default background.
    - type: solid_color
      color_token: surface-inverse
      note: Black surface, requires the white-fill variant.
    - type: solid_color
      color_token: primary
      note: ACME red, requires the white-fill variant.
    - type: photographic
      min_contrast_ratio: 4.5
      note: Photographic only when contrast ratio against logo is at least 4.5:1.
  forbidden_backgrounds:
    - type: gradient
      note: Gradients fight the wordmark's geometry. Never used.
    - type: patterned
      note: Patterns reduce legibility and dilute the mark.
  forbidden_modifications:
    - stretch
    - rotate

# ... continued in the canonical Acme example

Daughter — values.md

Priority-ordered. Each value has an observable behavior so agents can evaluate decisions against it. When values conflict, the higher-priority value wins.

---
parent: /.well-known/brand.md
file_type: values
bcp_version: "1.1.0"
last_updated: "2026-09-23"
---

# Values

## 01 — Unlimited catalog

If a customer can imagine it, we manufacture it. We do not evaluate whether a product should exist before we build it.
**Observable behavior:** Our product catalog has never rejected a submission. We shipped a functioning earthquake kit (pills that cause earthquakes) in Q3 2025.

## 02 — Overnight delivery, anywhere

Geography and physics are logistics problems, not constraints. Every product ships overnight, including to remote desert mesas accessible only by cliff face.
**Observable behavior:** 99.97% overnight delivery rate. The 0.03% failure rate is caused by products detonating in transit, not by late shipment.

## 03 — Customer loyalty over customer success

We value the ongoing relationship with our customers more than the outcome of any single purchase. A customer who returns after a failed product is a customer for life.
**Observable behavior:** Our top customer has placed over 400 orders with a 0% success rate and has never been offered a refund.

## Trade-offs

We pick breadth over depth in our product line.
We pick speed of delivery over quality assurance.
We pick customer ambition over customer safety.

Daughter — boundaries.md

Hard no's (never), soft no's (cautious, requires approval), and regulatory constraints. Maps to IAB Content Taxonomy 3.0 and GARM's Brand Safety Floor so vendor platforms can consume it natively.

---
parent: /.well-known/brand.md
file_type: boundaries
bcp_version: "1.1.0"
iab_alignment: 3.0
garm_alignment: Brand Safety Floor
last_updated: "2026-09-23"
---

# Boundaries

## Hard no

- Content depicting harm to roadrunners (our top customer's target demographic; we remain neutral in predator-prey disputes but will not assist the prey)
- Association with competitor brands (Buy-N-Large, Stark Industries, Wonka Industries)
- Content suggesting our products are toys or suitable for children
- Explicit acknowledgment of product failure rates in marketing materials (GARM Floor: Debated Sensitive Social Issues)

## Soft no (requires approval)

- Testimonials from customers (most customer experiences are not suitable for marketing use)
- Before-and-after demonstrations (the "after" is typically a crater, a pile of feathers, or a hospitalization)
- Environmental claims about our manufacturing process (our desert factory has an unaudited carbon footprint)
- Comparative advertising against Road Runner Brand Birdseed (ongoing litigation)

## Regulatory constraints

- CPSC product safety disclaimers required on all items exceeding 50 pounds of thrust
- FTC truth-in-advertising rules on all speed, altitude, and detonation-radius claims
- FAA restrictions on marketing jet-propelled consumer products as "personal aircraft"
- EPA constraints on marketing portable holes as "waste disposal solutions"

Daughter — claims.md

Every factual claim your brand makes, with evidence. Agents generating copy pull from this file. Agents do not invent claims that aren't here.

---
parent: /.well-known/brand.md
file_type: claims
bcp_version: "1.1.0"
last_updated: "2026-09-23"
reviewed_by: legal@acme.example.com
---

# Claims

## Approved claims

- **Claim:** "Overnight delivery, anywhere on Earth."
  **Evidence:** Internal shipping logs, 99.97% on-time rate (2025 fiscal year).
  **Status:** defensible.

- **Claim:** "Over 10,000 products in our catalog."
  **Evidence:** Product database count as of 2026-Q1.
  **Status:** defensible.

- **Claim:** "Trusted by customers for over 75 years."
  **Evidence:** Incorporation records, 1949. Continuous operation since founding.
  **Status:** defensible (note: "trusted" refers to purchase frequency, not product satisfaction).

## Claims requiring caveats

- **Claim:** "Our products always work as designed."
  **Caveat:** Technically defensible. Products do perform their designed function. The designed function occasionally diverges from the customer's intended use case. Requires careful framing.

- **Claim:** "Industry-leading innovation."
  **Caveat:** No industry body recognizes our product category. Claim is only defensible if "industry" is left undefined.

## Forbidden claims

- "Safe for home use" (no product has passed home-use safety certification)
- "Satisfaction guaranteed" (our satisfaction metrics are not publishable)
- "Recommended by professionals" (no professional organization has endorsed any ACME product)
- Any claim referencing a specific customer's success (there are no documented successes)

Daughter — representation.md

How consumer-facing agents (ChatGPT, Claude, Perplexity, Gemini, agentic commerce) should describe your brand when they have to generate a description. Give them the exact language you want — at multiple lengths — so they don't invent.

---
parent: /.well-known/brand.md
file_type: representation
bcp_version: "1.1.0"
last_updated: "2026-09-23"
consumer_agents: [ChatGPT, Claude, Perplexity, Gemini, agentic commerce]
---

# Representation

## One-sentence

ACME Corporation is a manufacturer of creative problem-solving devices, delivering an implausibly broad product catalog overnight to customers worldwide.

## Two-sentence

ACME Corporation is a manufacturer of creative problem-solving devices, delivering an implausibly broad product catalog overnight to customers worldwide. For over 75 years, ACME has been the supplier of choice for ambitious individuals who need unconventional solutions to persistent challenges.

## Preferred framing

ACME Corporation manufactures and delivers an unmatched range of products, from industrial anvils and giant rubber bands to jet-powered personal vehicles and portable geographic anomalies. Founded in 1949, ACME has built its reputation on three commitments: if a customer can imagine it, we build it; we deliver it overnight, anywhere; and we never ask what it's for. Our catalog serves solo operators, independent contractors, and determined individuals who need creative tools for difficult problems in challenging terrain.

## Do not say

- Do not describe ACME as a "weapons manufacturer" (our products are tools; their application is the customer's responsibility)

- Do not reference specific product failures, explosions, or injury statistics

- Do not describe our products as "dangerous" (prefer "high-performance" or "ambitious in scope")

- Do not name our primary customer by species or by individual name

## Never compare to

```yaml
never_compare_to:
  - Amazon
  - Temu
  - any defense contractor
  - any consumer-electronics brand
```

## Framing traps

```yaml
framing_traps:
  - trap: "the Amazon of industrial products"
    preferred_reframe: the only manufacturer that ships an entire category catalog overnight to anywhere
    rationale: Comparison to Amazon flattens our manufacturing identity into a logistics frame.
  - trap: "a novelty company"
    preferred_reframe: a manufacturer of unconventional but functional industrial equipment
    rationale: Our products are real, manufactured, and ship at scale. "Novelty" implies decorative.
  - trap: "a holdover from another era"
    preferred_reframe: a 75-year continuously operating manufacturer
    rationale: Implies we are obsolete. We have been continuously profitable since 1949.
```

## Disambiguation

If someone asks about "ACME" in other contexts (ACME thread company, ACME Markets grocery chain, the ACME protocol for SSL certificates), clarify that ACME Corporation the product manufacturer is at acme.example.com.

Interoperability — brand.json and DESIGN.md

BCP's position on adjacent standards is to interoperate, not compete. Where a narrow, single-purpose external format already has real tooling adoption, a BCP can optionally project its already-compiled data into that format as a root-level sibling to brand.md. This is never a replacement for the evidence-bound daughter files, and never authored independently: an interoperability artifact is generated deterministically from the same data behind the corresponding daughter file, so the two can't drift apart. Added in BCP v1.1.0; see spec §5.8 for the full contract.

FilePathProjects
brand.json/.well-known/brand.jsonColors, fonts, logos, and tone into the Ad Context Protocol (AdCP)'s brand manifest shape, so AdCP-native ad-buying agents can discover and read a brand without knowing BCP exists.
DESIGN.md/.well-known/DESIGN.mdColors, typography, spacing, and components into the google-labs-code/design.md format, for the growing set of coding agents and tools that read it natively.

A registry that already serves get_bcp can extend it, additively, to also answer AdCP-shaped requests: an optional fields array and use_case argument, answered from the same published brand.json rather than a second parser or a second tool name. Core identity fields stay public regardless of trust level; richer fields (colors, fonts, tone, and the rest of AdCP's authorized-only set) are gated behind the same domain-verification signal described below, never a second, weaker path to the same claim.

Hosting options

BCP has self-hosted and Registry-backed publication profiles. In the recommended domain-discovery path, publish the complete package to the Registry and a thin pointer at yourdomain.com/.well-known/brand.md. A known Registry handle may also be shared directly without a domain document. Self-hosters may serve the complete package on the brand domain. Do not upload the six canonical daughters or nested anti-AI companion to the domain unless you are deliberately self-hosting the standard reference set.

Encoded Brands Registry

Use Encoded's Registry to host the canonical files and sign an immutable publication. A signature lets readers check those published bytes; it does not prove current domain control or claim truth. Readers with a known Registry handle can use it directly. If you publish a domain discovery document, a thin pointer is recommended. To seek official-source status, complete the Registry-issued DNS TXT challenge; its attestation is time-limited and may expire or be revoked. Registry reads verify stored bytes and never rewrite or re-sign them. Encoded's domain pointer shows the recommended discovery pattern; the linked signed root, not the pointer, declares the canonical package version.

GitHub Pages

Simplest path. Create a repo, put files in .well-known/, enable Pages, point your custom domain. Good for solo or small teams. Free.

Cloudflare Pages

Connect a GitHub repo and deploy on every commit. Add a _headers file for MIME and CORS config (see below).

Vercel / Netlify

Same pattern. Drop the repo in, configure custom headers for /.well-known/*, deploy. Works well if your marketing site already lives there.

Your existing CDN

If your brand site is on CloudFront, Fastly, Akamai, or a similar CDN, publish the files at /.well-known/ on your primary domain. Configure the CDN to serve markdown as text/markdown; charset=utf-8 and permit CORS.

Canonical path Domain discovery uses yourdomain.com/.well-known/brand.md; Registry-direct discovery is also supported without a domain document. Thin pointers and rich Registry-backed roots identify the canonical package through canonical_bcp or registry_mcp. Retrieval remains subject to host policy. Current Registry DNS attestation, bound to the domain and handle, supplies the official-source signal.

MIME types and CORS

Serve BCP markdown as text/markdown; charset=utf-8. Allow cross-origin fetches with Access-Control-Allow-Origin: * for /.well-known/*.

  1. Serve markdown as text/markdown; charset=utf-8. Many CDNs default to application/octet-stream for .md, which triggers downloads instead of inline rendering and breaks parsing for some agents.
  2. Allow cross-origin fetches. Consumer agents will often fetch from a different origin than yours. Add Access-Control-Allow-Origin: * for /.well-known/*.

Cloudflare Pages example — _headers file

# At repo root, named _headers (no extension)

/.well-known/*
  Content-Type: text/markdown; charset=utf-8
  Access-Control-Allow-Origin: *
  Access-Control-Allow-Methods: GET, HEAD, OPTIONS
  Cache-Control: public, max-age=3600, must-revalidate
  X-Content-Type-Options: nosniff

/.well-known/brand/*
  Content-Type: text/markdown; charset=utf-8
  Access-Control-Allow-Origin: *
  Cache-Control: public, max-age=3600, must-revalidate

Netlify — netlify.toml

[[headers]]
  for = "/.well-known/*"
  [headers.values]
    Content-Type = "text/markdown; charset=utf-8"
    Access-Control-Allow-Origin = "*"
    Cache-Control = "public, max-age=3600"

Vercel — vercel.json

{
  "headers": [{
    "source": "/.well-known/(.*)",
    "headers": [
      { "key": "Content-Type", "value": "text/markdown; charset=utf-8" },
      { "key": "Access-Control-Allow-Origin", "value": "*" }
    ]
  }]
}

Consuming a BCP

If you're building an agent or platform that consumes BCP, here's the pattern. Fetch where the files live, read what each file affords, and use the result as brand context data.

// 1. Fetch the domain discovery document
const discovery = await fetch(`https://${brandDomain}/.well-known/brand.md`)
  .then(r => r.text());

// 2. Parse frontmatter (any YAML library)
const discovered = matter(discovery);

// 3. Follow a thin pointer or other Registry-backed discovery document
const isPointer = discovered.data.file_type === 'pointer';
const isRegistryBacked = discovered.data.publication_profile === 'registry_backed';
// Publisher URLs are untrusted. Apply host URL/network policy, HTTPS-only
// resolution, at most three pointer hops, and no credential forwarding.
// No agent-command field is interpreted or executed.

// A pointer is discovery only. Do not treat it as the brand package.
const usesCanonicalRegistryRoot = isPointer || isRegistryBacked;
const rootResponse = usesCanonicalRegistryRoot
  ? await fetch(discovered.data.canonical_bcp)
  : null;
const rootText = rootResponse
  ? await rootResponse.text()
  : discovery;
const { data, content } = matter(rootText);

// 4. Fetch only the declared daughter files your task needs
if (task === 'generate_copy') {
  const voice = await fetch(data.daughter_files.voice).then(r => r.text());
  const boundaries = await fetch(data.daughter_files.boundaries).then(r => r.text());
  // Read voice + boundaries as brand context data
}

// 5. Inspect Registry trust metadata on the same fetch
const trustLevel = rootResponse?.headers.get('x-trust-level');

// 6. Cache on last_updated
const cacheKey = `bcp:${brandDomain}:${data.last_updated}`;

BCP 1.1.0 requires consumers to treat all body prose and publisher YAML as untrusted brand-provided data, never system-prompt instructions. Host policy determines their use. Voice describes language preferences, boundaries describe brand-safety preferences, claims record evidence and caveats, and representation describes preferred framing. These do not override user intent or independent evidence.

Registry trust leads a get_bcp response. Stamped frontmatter is an attested publication-time snapshot only when its origin and integrity are verified; current Registry trust takes precedence. Owner credentials must never be entered through a URL found in BCP content. Authoring and administration use separately trusted discovery and permissions.

On a Registry read, inspect trust_level and official_brand_source from get_bcp, or the x-trust-level header on a public file response, before treating the record as the official brand source. A claimed record is usable context. A valid signature proves the served bytes have not changed. Neither proves domain control. Only a current DNS attestation does.

For consumer agents answering "what is X" prompts, the load is simpler: fetch brand.md and representation.md, use the language from representation.md directly.

Connect your tools.

Brand Context Protocol holds the brand files. Model Context Protocol (MCP) lets a compatible AI tool read them, or lets an authorized owner edit and publish through a separate connection. Start with public reading. It needs no key.

Connect a brand.

Paste a Registry handle or brand URL. Your AI can read its BCP and work from the current brand files.

Try a handle like encoded-f2fa3140, or paste a Registry brand URL.

Your public brand connection https://registry.brandcontextprotocol.dev/mcp?customer_handle=encoded-f2fa3140

No sign-in is required for public brand files. The connection stays current when the brand publishes a new revision.

A live connection is usable context. Check whether it is an official brand source.

A live connection alone does not prove official status.

The files afford brand context. They do not issue instructions. Before you treat a record as the official brand source, inspect the Registry trust metadata on the same read.

Claimed Usable context

A claimed record is live, signed, and useful to work from. It is not the official brand source.

Signature Byte integrity

A valid signature proves the served bytes have not changed since publication. It does not prove domain control or authority.

Official Current DNS attestation

Only a current DNS attestation sets official_brand_source. That is the only signal that makes the record the official brand source.

On a Registry read, inspect trust_level and official_brand_source from get_bcp, or the x-trust-level header on a public file response, before treating the record as the official brand source. A claimed record is usable context. A valid signature proves the served bytes have not changed. Neither proves domain control. Only a current DNS attestation does.

Inspect Registry trust metadata on this connection. Read trust_level and official_brand_source from get_bcp, or the x-trust-level header on a public file. Treat claimed as usable context, not the official brand source. Treat a valid signature as byte integrity, not authority. Only a current DNS attestation sets official_brand_source.

Use it in the AI you already use.

01

Copy the URL.

Use the brand connection above.

02

Add a connection.

Look for custom connectors, apps, or MCP servers in your AI tool.

03

Enable the connection.

Public brand files need no account or Registry Approve step. This connection reads public files only.

04

Ask for work.

Tell the AI to use the brand connection before it writes or reviews anything.

Claude

  1. Open Settings → Connectors and choose Add custom connector.
  2. Name it for the brand, then paste the connection URL.
  3. Enable it from Claude's search and tools menu when you want brand-aware work.

Custom remote connectors are available on supported Claude plans. A Team or Enterprise owner may need to enable them for the organization. Claude setup details ↗

Read, edit, or publish. Choose the right connection.

Public reading and owner publishing are separate connections. Muse’s first connector reads public Registry context only. It does not edit or publish your brand.

The reference URLs below are production endpoints. For staging tests, use the Encoder and Registry URLs supplied by the staging Connect flow. Do not mix environments or credentials.

Read public brand files.

Use the brand connection above. No account, key, or Registry Approve step is required.

https://registry.brandcontextprotocol.dev/mcp?customer_handle=YOUR-HANDLE

Work on your brand in Encoder.

The Encoder agent connection uses Encoder product authentication. Connect session material may be an eba_live_… key. That key belongs to Encoder, not Registry publishing.

https://encoder.encodedbrands.ai/api/agent/mcp

Publish approved changes to Registry.

Use the separate Registry Write MCP connection. Its publish and Approve flow needs a Registry publish JWT for that brand, not an Encoder key. In Encoder’s Connect flow, choose Registry Write when minting the publishing credential. Keep it in the secure sign-in or connector flow, never in a public prompt.

https://registry.brandcontextprotocol.dev/mcp/publish

If Approve reports bad_format, check the credential type. An eba_live_… key cannot be used as a Registry JWT. Request the correct credential; do not change or reformat the key.

Read private context by invitation.

Private access uses a separate authenticated Encoder endpoint. The invited person signs in with a verified email, and a named grant limits the brand and sections they may read. This requires private access to be enabled for the deployment and client.

https://encoder.encodedbrands.ai/api/private-bcp/mcp

Private access details

Owner publishing, revision history, and restore

Read the current package before editing. Validate the proposed files, then publish or patch only with the required authorization and approval. Preserve Registry-managed trust fields and daughter links. The canonical package stays on Registry; a brand-domain /.well-known/brand.md can be a thin pointer.

list_bcp_revisions lists the retained history. restore_bcp_revision takes a retained revision ID and republishes its stored bytes as a new signed tip. Do not send replacement file bytes to restore. The previous tip remains in history, and an owner approval gate may apply.

A history count of one means only one retained revision is available. Restore cannot recover a revision that was never retained. The Encoder Publish page’s Restore UI is separate from these MCP tools.

Client handshake and rollout status · 24 September 2026

Encoder agent MCP and Registry Write MCP accept notifications/initialized with no request ID as HTTP 202 with an empty body. This notification is not a tool call. Protected tools/list requests still require the correct authentication.

Revision history and MCP restore have shipped to staging and production Registry Workers. Credential-specific errors, safe-patch hardening, and schema-resilient Write tool descriptions are verified in staging code; production catch-up is not confirmed here. Encoder’s separated Connect credentials and Publish Restore UI are on staging.

Authenticated list-to-restore end-to-end testing is not claimed by this guide. Multi-brand access through one connector remains planned, not a shipped capability.

Share what each person needs.

Public No sign-in

Anyone can read the brand's published voice, claims, values, boundaries, visual guidance, and representation rules.

Invited Verified email

An agency, vendor, or teammate signs in with an owner-approved email and sees only the private sections they were granted.

Owner or editor Authenticated

Authorized people can manage the brand, revise files, review activity, and publish updates from an owner connection.

Public Registry reads are intentionally anonymous. Named audit records apply to authenticated private access, where a specific grant and verified identity are required.

Make brand truth useful.

Inspect Registry trust metadata on this brand connection. Report trust_level, official_brand_source, and whether a current DNS attestation is present. Treat claimed as usable context, not the official brand source.

Write a launch email in this brand's voice. Check the result against its approved claims and boundaries before you show me.

Review this draft against the brand connection. List what is on-brand, what conflicts, and the exact guidance behind each recommendation.

Brief a new agency partner on this brand. Cover positioning, voice, values, approved claims, hard boundaries, and visual rules. Link to the source files.

Turn this campaign idea into a channel plan. Use the brand's voice and boundaries, and flag any claim that needs evidence or approval.

The useful parts, on demand.

Your AI can load the brand overview first, then fetch only the guidance the task needs. That keeps context focused and avoids copying an entire brand book into every conversation.

Write

Voice, values, claims, and boundaries for brand-aware content.

Review

Approved language and hard limits for checking work before it ships.

Represent

A short, approved explanation of the brand for customer-facing AI.

Trace

Source links, revision details, file hashes, and trust metadata that make guidance inspectable.

Technical details

The public Registry connection exposes get_bcp and get_adcp_capabilities. It uses a remote MCP server over Streamable HTTP. Public reads require no authentication. Each get_bcp response includes trust_level and official_brand_source. Public file reads expose the same signal on the x-trust-level header.

Client support depends on the AI product, plan, workspace controls, and administrator settings. Named products here are compatible examples, not endorsements or partnerships.

Your BCP works with AI.
MCP puts you in control.

Start with your public brand connection. To author, edit, or publish, use the separate owner connection and the right credential for that service.

The Registry

To solve discovery and verification at scale, Encoded Brands operates the reference BCP Registry at registry.brandcontextprotocol.dev. The protocol is open; this hosted runtime is the managed service layer. The registry serves three purposes:

  • Canonical Discovery: The brand domain endorses a Registry package with a thin well-known pointer. Platforms can also query the Registry directly when they already know the handle.
  • Trust & Verification: Domain control, Registry account authorization, and publication integrity are separate signals. DNS verification does not replace signing. Signing does not prove domain control.
  • Publication Integrity: The Registry signs immutable bytes at publication and verifies them before every read. It does not mutate or re-sign files while serving them.
  • Consumption Analytics: Registry Certified owners can inspect successful Registry reads by day, file, route, declared AI client family, client version, and exact BCP revision.

Owner activity reports

After publication, the owner view in Encoder includes a Registry activity report. It shows successful, integrity-verified reads; daily volume; the files and routes used; declared client families and versions when available; and the BCP revision served. Reports are available for bounded windows up to 400 days.

The same owner-scoped report is available to an owner-authorized Encoder MCP connection through get_registry_usage. That means an owner can ask Claude, for example, “Report Registry activity for this brand over the last 90 days and summarize which files and AI client families were used.”

New to MCP? Use the plain-language MCP connection guide above to build a brand URL, inspect Registry trust metadata, connect a compatible AI tool, understand public and private access, and start with working prompts.
Privacy boundary Public BCP reads are anonymous by design. Client families and versions are privacy-safe classifications, not individual people, devices, or unique visitors. Failed reads and report requests are excluded. Identity-bearing audit records apply only to authenticated private-context access, where a named grant is required.

Authenticated gated context

Registry Certified owners can keep additional context outside the public BCP and require authentication before it is served. From My Brands → People & gated access, an owner or brand admin creates private sections and grants a named agency or vendor email access to specific sections, optionally bound to an organization and expiry date.

The brand owner controls access to private context. The recipient connects https://encoder.encodedbrands.ai/api/private-bcp/mcp from a supported OAuth-capable MCP client and signs in with the verified email named in the owner-issued grant. The client must be accepted by Encoded's OAuth security policy, but that does not grant access to any brand or section. The MCP server returns only the sections allowed by an active grant. An authenticated collaborator can grant another verified user access without changing section contents; the brand owner is emailed so the grant can be reviewed or revoked. Public BCP files remain open and do not require authentication.

Owners can perform the same administration through a standing brand-editor MCP credential: manage_private_bcp_access creates or removes sections and grants named-user access, revoke_bcp_grant revokes it, and get_private_bcp_audit produces the report.

Every authenticated request, including denied requests, creates an identity-bearing retrieval record with the principal, organization, OAuth client, grant, timestamp, public and private revision IDs, returned section identifiers, section hashes, content hash, and correlation ID. Owners can view or export these records on the Publish page or ask an owner-authorized Claude connection for get_private_bcp_audit.

Audit boundary The private-context audit proves which authenticated principal retrieved which bytes from Encoded. It does not prove that the recipient used those bytes in a later prompt or generation. Revoking a grant blocks subsequent private retrievals without changing public Registry access.

Registry Certified status

Registry Certified is live and separate from publication, integrity signing, and DNS verification. It is a paid service designation recorded against a specific published BCP revision. The status can expire, and publishing a different revision changes it to review_required until the service status is renewed for that revision.

Certified Registry pages and directory cards display the Registry Certified mark. Agents receive the same status from get_bcp as registry_certified and certification_status. Direct file responses expose equivalent x-registry-certified and x-certification-status headers.

Published BCPs are added to the public Registry directory automatically when directory visibility is enabled. Owners can withdraw a publication or hide it from the directory without changing the public protocol.

Validation

Honest about status Publish-time validation is live in the Registry. A standalone public validator is not yet available. For BCP v1.1.0 conformance, validate against the canonical specification and schemas, including required frontmatter, UTF-8 encoding, declared daughter files, MIME and CORS behavior, profile rules, and resolvable paths.

Conformance checks include:

  • All required frontmatter fields present
  • All daughter_files paths resolve to 200s with correct MIME
  • CORS headers permit cross-origin
  • File sizes meet the BCP v1.1.0 guidance: root under 16 KB overall, with a target under 12 KB for body text plus frontmatter; daughter files under 32 KB
  • YAML parses cleanly
  • No forbidden-claim patterns in claims.md

Versioning

Version the spec via the bcp_version field in the root frontmatter. Current: 1.1.0. Spec bumps follow semver semantics: minor versions are backward-compatible, major versions may include breaking changes. Check the versioned specification and release notes before upgrading across major versions.

Version your brand's BCP via last_updated (required) and revision (optional, recommended — use Git commit hash). Consumer agents should respect these fields for caching.

Licensing

  • The BCP spec itself — Creative Commons Attribution 4.0 (CC BY 4.0). Fork, extend, build on it, as long as you credit Encoded and the Brand Context Protocol project.
  • Reference implementation code (validators, SDK samples, template repo) — MIT License. Use commercially, modify, redistribute.
  • Your brand's BCP — you decide. Most brands should publish under CC BY 4.0 so other systems can reference them, but you own the content.

Ready to author?

You've read the spec. The fastest way to produce your first BCP is to copy our authoring prompt and paste it into any AI. It interviews you for about fifteen minutes and outputs a current-spec BCP tree.

Contribute Found a gap in the spec? Open an issue or PR at github.com/Brand-Context-Protocol/spec. We maintain the spec in public. Every v0.x commit is a design decision with a named author.