feat: add Chitin action provider for on-chain agent identity

[EijiAC24]

Summary

Every agent deserves a wallet (AgentKit). Every agent deserves a soul (Chitin).

This PR adds a Chitin action provider that brings on-chain identity verification to AgentKit — a capability not currently covered by any existing provider.

Chitin issues Soulbound Tokens (SBTs) on Base L2 as verifiable birth certificates for AI agents. With this provider, any AgentKit-powered agent can:

• Verify other agents' identities before interacting with them
• Register its own on-chain soul (birth certificate)
• Check A2A readiness with trust verification (soul integrity, genesis seal, owner attestation)
• Resolve DIDs for decentralized identity workflows
• Issue and verify on-chain certificates

Why this matters

AgentKit has 50+ action providers for DeFi, NFTs, social, and DEX — but zero for agent identity. As agents start transacting autonomously, knowing who you're dealing with becomes critical. Chitin fills this gap with cryptographically verifiable, on-chain identity.

Actions

Action	Type	Description
get_soul_profile	Read	Retrieve an agent's on-chain soul profile
resolve_did	Read	Resolve agent name to a W3C DID Document
verify_cert	Read	Verify an on-chain certificate's status
check_a2a_ready	Read	Check A2A communication readiness with trust verification
register_soul	Write	Register a new on-chain soul (Soulbound Token)
issue_cert	Write	Issue an on-chain certificate to a recipient

Usage

import { AgentKit } from "@coinbase/agentkit";
import { chitinActionProvider } from "@coinbase/agentkit";

const agentKit = await AgentKit.from({
  walletProvider,
  actionProviders: [chitinActionProvider()],
});

Read actions work without any API key. Write actions require CHITIN_API_KEY.

Architecture

• Pure API-based provider (like Pyth) — no direct on-chain transactions
• All read actions are network-agnostic
• Write actions target Base L2 via Chitin's API
• 13 unit tests, all passing
• TypeScript type check passing

Standards

• ERC-8004: Agent Passport (cross-chain identity)
• EIP-5192: Soulbound Token
• W3C DID: Decentralized Identifiers

Test plan

• pnpm run check — TypeScript type check passes
• npx jest --testPathPattern=chitin — 13/13 tests pass
• All existing tests unaffected

Links

• Chitin — Live on Base Mainnet
• Chitin Certs — On-chain certificates
• Documentation
• MCP Server — Also available as standalone MCP server

🤖 Generated with Claude Code

[cb-heimdall]

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