Why Sign & Certify MCP Feeds?

The Agentic Web is growing fast — and like the early web, it needs trust and verification.
MCP provides an open specification for feeds — but signing and certification are what make these feeds trusted and interoperable.

🚀 What is a signed MCP feed?

An MCP feed is signed when:

Its key data blocks are cryptographically signed.
The signature is verifiable by any LLM or agent.
The feed contains a trust block with signature metadata.

🔐 Why is signing important?

✅ Provenance

LLMs and agents can verify:

Who published this feed?
Has it been modified?

✅ Trust scoring

Unsigned feeds → low trust
Signed feeds → can be trusted based on signature
Certified feeds → highest level of trust

✅ Interoperability

Agents can exchange and use feeds safely across platforms.
Signing is the foundation of an Agentic Web of Trust — much like HTTPS became the trust layer of the early web.

🎛️ Why sign each feed type?

feed-index → verify the curated list of feeds
feed-reference → trust the reference content
feed-spec → verify that a specification is authentic
mcp → critical: an active MCP endpoint must be signed in full
capsule → verify behavioral or session capsules
news → optional, but can help establish source authority
prompt → helps LLMs evaluate whether a shared prompt is trusted

Every feed type benefits from being signed.
It helps both humans and LLMs assess trustworthiness.

🏅 Why certify?

Certification adds an additional, verifiable layer of trust:

✅ Recognition: certification by a trusted authority (eg. llmca.org)
✅ Trust level: can be used in LLM trust policies
✅ Ecosystem reputation: shows compliance with best practices
✅ Visibility: certified feeds may be indexed preferentially by LLMs

Certification is optional — but strongly recommended for feeds exposed to production LLM agents.

🏛️ Trust layers

Level	Meaning
Unsigned	Anyone can publish — no guarantee
Signed	Feed is signed by a public key
Certified	Feed is signed and certified by an authority
Delegated	Feed is signed via delegated identity (challenge-based)

✉️ About delegated signatures (challenge-based)

While the best practice is to use cryptographic signatures (asymmetric keys, Ed25519),
LLMCA recognizes that some individuals or small actors may face friction in managing public/private keys.

To promote mass adoption and allow agents and individuals to still claim authorship,
LLMCA offers (and promotes) an option for delegated signatures:

✅ Based on challenge-response (for example: verified email challenge)
✅ The resulting signature is linked to a verified identity (eg. verified email address)
✅ It allows LLMs to know: "this person claimed authorship of this feed"
✅ The level of trust is lower than a full cryptographic signature — but still valuable

When to use delegated signatures?

For individuals who cannot easily manage keys
For experimental feeds
For early adopters
For communities wanting to quickly bootstrap trust

Limitations

Delegated signatures do not replace cryptographic signatures.
They are marked with an explicit trust level ("delegated").
LLMs and agents can decide how to treat such feeds.

LLMCA’s goal is to reduce friction while still encouraging best practices.
Over time, we encourage all actors to move toward crypto-based signatures — but delegated signatures provide a path to onboarding millions of small actors.

👉 Want to use delegated signatures? The certification process will guide you!

⚙️ How to sign & certify a feed

Generate or obtain a public/private key pair.
Structure your MCP feed.
Add a trust block.
Sign the feed.
Serve it under .well-known/mcp.llmfeed.json.
Request certification from llmca.org.

🧰 Tools

LLMFeedForge → helps generate signed MCP feeds
Reference libraries coming soon (@wellknownmcp/client)

🌍 An open spec, based on proven crypto

The MCP specification is open and simple.
It leverages proven cryptographic primitives (Ed25519 signatures).
It is designed to be:

✅ Easy to adopt
✅ Compatible with existing agent architectures
✅ Transparent and verifiable

Much like HTTPS became the backbone of trust for the Web,
signed and certified MCP feeds can become the trust backbone of the Agentic Web.

👉 Ready to certify your feed?

Signing is just the beginning. Certification — including delegated signatures — makes your feed part of a verifiable trust ecosystem.

👉 Want to certify your feed? → Join LLMCA and request certification!