AGA - Attested Governance Artifacts

Cryptographic runtime governance for AI agents and autonomous systems.

Status: published to npm; this release carries SLSA build provenance (check it: npm audit signatures). The server tools and the aga-proxy emit the canonical SEP evidence bundle, verifiable offline by the published @attested-intelligence/aga-verify and the reference verifier aga-receipt-spec/verify/verify-sep.mjs. Since 3.2.0 the verifier is algorithm-agile and ships a post-quantum profile: v1 Ed25519-SHA256-JCS (the default the gateway emits) and v2 ML-DSA-65+Ed25519-SHA256-JCS (a NIST FIPS-204 ML-DSA-65 + RFC-8032 Ed25519 composite, both must verify), selected per-bundle by the algorithm field with a VERIFIED / FAILED / UNSUPPORTED_PROFILE trichotomy. Pre-3.0 releases (a legacy continuity-chain bundle that does not verify under the SEP verifier) are deprecated; use ^3.0.0. Claim scope and residual attack surface are documented honestly in THREAT_BOUNDARY.md.

# This package IS the AGA MCP server (TypeScript, runs over stdio). Use it from any MCP client:
npx -y @attested-intelligence/aga-mcp-server

A Python companion SDK (aga-governance) is documented in the Python SDK section below.

Verify this yourself (don't take our word)

You do not have to take any of this on faith. The repo ships the reference verifier, the canonical vectors, and sample bundles, so you can check one offline right now, with no network and no callback to us:

git clone https://github.com/attestedintelligence/aga-mcp-server
cd aga-mcp-server
# A canonical SEP bundle verifies; a one-byte-tampered copy is rejected.
node aga-receipt-spec/verify/verify-sep.mjs fixtures/valid_minimal.json   # OVERALL: VERIFIED (integrity only; no key pinned)
node aga-receipt-spec/verify/verify-sep.mjs fixtures/tampered.json        # OVERALL: FAILED

The published @attested-intelligence/aga-verify CLI renders the identical verdict, and npm run conformance:cross-stack (first: npm run build && npm --prefix independent-verifier run build) proves six v1 verifier configurations, spanning three independent toolchains (JavaScript, Go, and Python, including a pure-stdlib, no-third-party-crypto path), agree on all 57 cross-stack cases; npm run conformance:cross-stack-v2 proves two genuinely independent-language oracles (@noble/JS and CIRCL/Go) agree on the v2 composite corpus. For a full trust-free reproduction (build the package yourself, reproduce the published tarball byte-for-byte, re-run every gate), see the REVIEWER_GUIDE.md (a command-by-command self-service path), REPRODUCIBILITY.md, and the step-by-step SKEPTICAL_AUDITOR.md. This release carries SLSA build provenance, checkable with npm audit signatures.

Related MCP server: agent-sudo-mcp

What This Does

Every tool call an AI agent makes passes through the AGA gateway. Each call is evaluated against policy, and the decision (PERMITTED or DENIED) is recorded as a signed, hash-linked governance receipt. Receipts are collected into evidence bundles that any third party can verify offline using standard cryptography.

Record. Prove. Verify.

Scope: a verified bundle proves the integrity of the receipts present: each is authentic, correctly ordered, Merkle-included, and (when a key is pinned) provenance-bound. It does not prove non-omission (that every action the agent took was logged); completeness is bounded by the tamper-evidence of the interception point, which is outside the bundle. See KNOWN_LIMITATIONS.md for the full honest boundary, and THREAT_BOUNDARY.md for the per-field detail.

Use with Claude Desktop

Add to your Claude Desktop MCP config (claude_desktop_config.json):

{
  "mcpServers": {
    "aga": {
      "command": "npx",
      "args": ["-y", "@attested-intelligence/aga-mcp-server"]
    }
  }
}

Claude can then seal artifacts, measure integrity, generate evidence bundles, and verify compliance through natural language.

Persist the signing key (do this first)

By default the gateway signs with an ephemeral key that rotates on every restart. That is fine for a first look, but evidence-bundle provenance cannot be pinned across restarts (and the server warns about it on stderr). Set one stable 64-hex Ed25519 seed so provenance stays pinnable:

# generate a seed once (32 random bytes, hex)
node -e "console.log(require('node:crypto').randomBytes(32).toString('hex'))"

Provide it via AGA_GATEWAY_KEY, or AGA_GATEWAY_KEY_FILE (a path to the seed). In Claude Desktop, add an env block:

{
  "mcpServers": {
    "aga": {
      "command": "npx",
      "args": ["-y", "@attested-intelligence/aga-mcp-server"],
      "env": { "AGA_GATEWAY_KEY": "<your-64-hex-seed>" }
    }
  }
}

Keep the seed secret and out of version control; see DEPLOYMENT.md for key handling.

MCP Tools (15)

measure_behavior is detective-only by default: it observes tool-usage patterns and records a signed, provable drift finding, but does not block. Enforcement (drift → quarantine) is opt-in via enforce=true and off by default. Hard governance decisions (PERMITTED/DENIED) are made by the portal/PEP, not the behavioral monitor.

Quick Start: verify a bundle offline

A bundle this package emits (via the generate_evidence_bundle MCP tool) is a canonical SEP bundle. Verify it offline, with no network and no callback to us:

# Published verifier CLI — ships on npm, nothing to clone. Pin the gateway key (from get_server_info) to prove provenance.
npx -y @attested-intelligence/aga-verify evidence-bundle.json --pubkey <gateway-public-key>

# Or, from a clone of this repo, the zero-dep reference verifier (Node 18+) renders the identical verdict:
node aga-receipt-spec/verify/verify-sep.mjs evidence-bundle.json --pubkey <gateway-public-key>

The published @attested-intelligence/aga-verify CLI is the shipped path (the older forgeable 1.0.0 is deprecated); the reference verify-sep.mjs renders the identical verdict from a repo clone. Without --pubkey you get an integrity-only result (issuerVerified=false); pin the key to also prove who issued it. See THREAT_BOUNDARY.md §3.7. A hosted browser verifier is linked under Links.

The reference §6 algorithm is implemented in three languages: JavaScript (aga-receipt-spec/verify/verify-sep.mjs), Go (verify.go, stdlib crypto/ed25519), and Python (verify.py, pure-stdlib RFC-8032 Ed25519). A cross-stack harness (npm run conformance:cross-stack; first: npm run build && npm --prefix independent-verifier run build) proves all three, plus the in-server engine and aga-verify, render identical verdicts on the canonical vectors (valid, adversarial, and every small-order forgery). The v2 composite profile (ML-DSA-65+Ed25519-SHA256-JCS) is held to the same bar by a second harness (npm run conformance:cross-stack-v2): a @noble/JavaScript engine and a CIRCL/Go oracle, two genuinely independent toolchains, render identical verdicts on the pinned v2 corpus, and the reference v1 verifier (verify-sep.mjs/verify.py/verify.go) returns UNSUPPORTED_PROFILE (exit 3) on a v2 bundle, signalling "profile not implemented" rather than a misleading "invalid". (The published aga-verify CLI does not implement this profile trichotomy: on a v2 bundle it returns FAILED (exit 1). Use exit 3 as the unsupported-profile signal only with the reference verifiers.)

Check-name mapping across implementations

The JS reference verifier and the Python SDK (aga-governance) decompose the same seven-check verification differently. Overall verdicts and exit codes agree on every conformance-corpus case (re-proven 2026-07-01: 10/10 cells across pristine/tampered bundles with unpinned, correct, and wrong keys); the sub-check that reports a given tamper can differ:

Known decomposition difference: the JS reference recomputes every Merkle leaf from full receipt content, so a receipt-signature tamper also fails merkle_and_bijection; the Python verifier surfaces the same tamper in receipt_signatures_valid, chain_integrity_valid, and bundle_consistent while its merkle_proofs_valid can remain true. Neither is looser: the bundle fails in both stacks, exit 1. One input-handling difference is deliberate: a malformed --pubkey pin is a usage error (exit 2) in the Python SDK, while the JS reference treats a malformed pin as unpinned; the Python behavior is strictly tighter.

How It Works

AI Agent                  AGA Gateway                    Verifier
   |                          |                              |
   |-- tools/call ----------->|                              |
   |                    [Evaluate Policy]                    |
   |                    [Sign Receipt]                       |
   |                    [Chain to Previous]                  |
   |<-- PERMITTED/DENIED -----|                              |
   |                          |                              |
   |                    [Export Bundle]                       |
   |                          |--------- evidence.json ----->|
   |                          |                  [Verify Signatures]
   |                          |                  [Verify Chain + Order]
   |                          |                  [Verify Merkle Tree]
   |                          |                  [Verify Signed Checkpoint]
   |                          |                  [PASS / FAIL]

MCP Governance Proxy

Run AGA as a transparent proxy between any MCP client and any MCP server. Every tool call gets evaluated against policy and produces a signed receipt.

# Start the proxy (the `aga-proxy` bin) in front of an upstream MCP server.
# stdio upstream = the hardened default (the upstream is a child process, not network-reachable).
npx -p @attested-intelligence/aga-mcp-server aga-proxy start \
  --upstream "npx -y @modelcontextprotocol/server-filesystem /tmp/test" --profile standard

Exporting the evidence bundle from a running proxy

The proxy records receipts in its own process and keeps the SEP ledger in memory. To make that live ledger reachable from a separate shell, aga-proxy start opens a loopback-only control channel — an HTTP listener bound to 127.0.0.1 (never a routable interface), on its own port (default 18801, override with --control-port), distinct from the agent-facing proxy port (18800). It exposes only read routes (/export, /status, /receipts); nothing on it mutates policy or state, and it is unreachable off-host by construction (the loopback bind is the guarantee). The proxy writes the chosen control port to ~/.aga-proxy/control.json alongside proxy.pid.

A separate aga-proxy export invocation reads that file and fetches the same signed bundle the running proxy would emit:

# Terminal A — start the proxy in front of an upstream MCP server
npx -p @attested-intelligence/aga-mcp-server aga-proxy start \
  --upstream "npx -y @modelcontextprotocol/server-filesystem /tmp/test" --profile standard

# Terminal B — export the live ledger from a different shell, then verify it offline
npx -p @attested-intelligence/aga-mcp-server aga-proxy export -o evidence.json
npx -y @attested-intelligence/aga-verify evidence.json --pubkey <gateway-public-key>

If no proxy is running, aga-proxy export prints no running proxy found; start it first, or export from within the session and exits non-zero — it never emits an empty or placeholder bundle. Within the MCP server session you can also call the generate_evidence_bundle tool and save the returned JSON.

In-memory ledger: the exported bundle is the durable cryptographic record, but the live in-process chain does not survive a proxy restart. This flow makes the live ledger reachable from another process; it does not add cross-restart persistence, which needs the persistent (SQLite) backend and remains roadmap (see KNOWN_LIMITATIONS.md).

The proxy intercepts tools/call requests, evaluates them against a sealed policy, and generates a signed SEP receipt for every decision. Permitted calls are forwarded to the downstream server; denied calls return an MCP error and never reach it. Every decision is hash-linked and checkpoint-bound into a tamper-evident bundle. (Methods other than tools/call aren't policy-evaluated, but non-benign ones are recorded as signed passthrough receipts for auditability, and an optional denylist can reject them; see THREAT_BOUNDARY.md §3.2.)

Three built-in policy profiles:

• permissive - log everything, block nothing (default)

• standard - rate limits + blocks destructive operations

• restrictive - explicit tool allowlist, all unknown tools denied

Verification (canonical SEP 3.0; normative §6 algorithm in aga-receipt-spec/verify/verify-sep.mjs)

1. Structural floor - Bundle declares Ed25519-SHA256-JCS, public key well-formed (all small-order encodings + non-canonical y ≥ p rejected), receipts.length > 0, proof count = receipt count

2. Receipt Signatures - Ed25519 over JCS-profile canonical JSON, sorted-key (signature field excluded)

3. Chain + ordering - Each receipt's previous_receipt_hash = leaf of the preceding receipt; non-decreasing timestamps

4. Merkle Proofs - Recompute every leaf from receipt content, walk siblings/directions to one root, leaf indices form the complete 0..N-1 bijection

5. Signed checkpoint - Verify the gateway-signed checkpoint binding merkle_root, leaf_count, and chain head (this makes the no-prefix construction truncation-safe)

6. Provenance (when a key is pinned) - public_key == expected key; otherwise integrity-only is reported

Cryptographic Primitives

Live Gateway

A demo gateway is deployed on Cloudflare Workers (a separate deployment that may track its own version; treat it as a convenience mirror, and always verify what it returns offline against a pinned key, not as the canonical artifact):

# Check status
curl https://aga-mcp-gateway.attested-intelligence.workers.dev/health

# Export evidence bundle
curl https://aga-mcp-gateway.attested-intelligence.workers.dev/bundle -o evidence-bundle.json

Python SDK

pip install aga-governance

from aga import AgentSession

with AgentSession(gateway_id="my-gateway") as session:
    session.record_tool_call(
        tool_name="search_web",
        decision="PERMITTED",
        reason="tool in allowlist",
        request_id="req-1",
    )
    bundle = session.export_bundle()
    result = session.verify()
    assert result["overall_valid"]

Test Suite

Automated tests across TypeScript and Python, plus a conformance corpus:

• TypeScript MCP server: 384 automated tests (vitest), including provable-denial and behavioral-monitor regressions

• SEP conformance corpus: npm run test:conformance (valid → VERIFIED, negatives → FAILED)

• Python companion SDK: the separately-published aga-governance PyPI package (install + smoke-checked here; its full pytest suite runs from the source tree)

npm test                              # TypeScript tests (vitest)
npm run test:conformance              # SEP conformance corpus
pip install aga-governance && python -c "import aga; print(aga.__version__)"   # Python SDK smoke check

Benchmarks

Receipt-format determinism is reproducible here: npm test runs the cross-language vectors, and npm run conformance:cross-stack (first: npm run build && npm --prefix independent-verifier run build) shows the six v1 verifier configurations (across three independent toolchains: JS, Go, Python) agree on the canonical 57-case corpus, while npm run conformance:cross-stack-v2 shows the two independent-language v2 oracles agree on the composite corpus.

Project Structure

src/
  sep/                 # Canonical SEP evidence engine: single source of truth (canon, merkle, receipt, checkpoint, bundle, verify)
  core/                # Governance primitives (portal, artifact, attestation, disclosure, delegation, behavioral) + internal continuity-chain profile
  crypto/              # Internal continuity-chain crypto: Ed25519 (node:crypto), SHA-256/blake2b, salt
  proxy/               # MCP governance proxy (transparent interception + policy enforcement; emits SEP bundles)
  middleware/          # Governance PEP wrapper (records a signed PERMITTED/DENIED receipt per governed call)
independent-verifier/  # @attested-intelligence/aga-verify: standalone SEP verifier, zero AGA imports
scenarios/             # Demo scenarios (SCADA, autonomous vehicle, AI agent) that emit SEP bundles
tests/                 # TypeScript test suite (384 automated tests)

Links

• Website

• Technology

• Live Verifier

• Trust and Scope

• Diligence Materials

• MCP Server (npm)

• Python SDK (PyPI)

Security

See SECURITY.md for vulnerability reporting.

Contributing

See CONTRIBUTING.md for development setup and guidelines.

License

MIT

Attested Intelligence Holdings LLC