agentrust-io demos

Runnable demos for cMCP and TRACE. Three demos, ~4 minutes total.

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Prerequisites

pip install cmcp-runtime

cmcp-runtime includes all dependencies (starlette, uvicorn, cmcp-verify). All demos use CMCP_DEV_MODE=1 (software-only TEE, no hardware required). The local MCP server performs real filesystem operations on ./workspace/.

Set a bearer token (the cMCP Runtime requires one):

# bash
export CMCP_BEARER_TOKEN=demo-token

# PowerShell
$env:CMCP_BEARER_TOKEN = "demo-token"

Each demo has a run.py (works on any OS) and a run.sh (bash only). Server and cMCP Runtime logs are written to *.log files in the demo directory, not the terminal.

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Demo 1 -- cMCP in action (~90 seconds)

The agent calls three tools through the cMCP gateway. Cedar policy is enforced for every call. At session close, the gateway produces a signed TRACE claim carrying the policy bundle hash.

On real Intel TDX hardware, the policy bundle hash flows into RTMR[2] at startup. Here it appears in trace.policy.bundle_hash in the claim.

python demo-01-cmcp-in-action/run.py

What you see:

• cMCP starts, measures the policy bundle hash
• write_file: Cedar allows it, real file written to workspace/hello.txt
• read_file: Cedar allows it, reads the file back
• list_dir: denied by Cedar policy (HTTP 403, error_code: POLICY_DENY)
• TRACE claim shows runtime.platform, runtime.measurement, policy.bundle_hash
• Claim saved to workspace/trace-claim.json (needed by demos 2 and 3)

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Demo 2 -- Policy swap = attestation failure (~90 seconds)

The operator loads a different Cedar policy bundle (v1 vs v2). The claim's policy.bundle_hash changes. A verifier that pinned the v1 hash rejects v2 claims with POLICY_HASH_MISMATCH.

On real TDX hardware, the policy hash flows into RTMR[2] at startup -- the TEE measurement itself changes, not just a field in the claim.

Requires demo 1 to have run first (reads workspace/trace-claim.json).

python demo-02-policy-swap/run.py

What you see:

• v1 and v2 bundle hashes printed (visibly different SHA-256 values)
• write_file is DENIED under v2 policy (new Cedar forbid rule)
• cmcp verify on the v1 claim with v2 hash -> POLICY_HASH_MISMATCH
• cmcp verify on the v1 claim with v1 hash -> passes

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Demo 3 -- Offline TRACE verification (~60 seconds)

The signed TRACE claim from demo-01 is verified with no gateway, no server, and no network call. Only cmcp_verify and the hashes embedded in the claim are used.

Requires demo 1 to have run first.

python demo-03-offline-trace/run.py

What you see:

• Claim fields printed: runtime.platform, runtime.measurement, policy.bundle_hash
• All cryptographic checks pass (schema, signature, policy hash, catalog hash, audit chain)
• hardware_attestation is in unverified_fields (software-only mode -- on real TDX it would also be verified)
• No connection made to any server

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Structure

demos/
+-- README.md
+-- requirements.txt
+-- server/
|   +-- server.py               # Plain HTTP JSON-RPC 2.0 server: write_file, read_file, list_dir
|   +-- requirements.txt
+-- workspace/                  # Files written by demos (created at runtime)
+-- demo-01-cmcp-in-action/
|   +-- cmcp-config.yaml
|   +-- catalog.json            # Approves write_file, read_file, list_dir
|   +-- policies/               # Cedar: permit write_file+read_file, forbid list_dir
|   +-- call.py                 # Demo agent: calls tools, closes session, saves claim
|   +-- run.py                  # Cross-platform launcher (use this)
|   +-- run.sh                  # bash-only launcher
+-- demo-02-policy-swap/
|   +-- catalog.json
|   +-- cmcp-config.yaml        # Points to policies-v1/
|   +-- cmcp-config-v2.yaml     # Points to policies-v2/
|   +-- policies-v1/            # Cedar: permit all
|   +-- policies-v2/            # Cedar: deny write_file (hash differs from v1)
|   +-- check_hash.py           # Computes and compares bundle hashes
|   +-- run.py                  # Cross-platform launcher (use this)
|   +-- run.sh                  # bash-only launcher
+-- demo-03-offline-trace/
    +-- verify.py               # cmcp_verify.verify_trace_claim (no network)
    +-- run.py                  # Cross-platform launcher (use this)
    +-- run.sh                  # bash-only launcher

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How it connects

Agent (call.py)
     |
     v  POST /mcp  Authorization: Bearer <token>
[cMCP runtime :8443]  <--  Cedar policy bundle (hash -> RTMR[2] on TDX)
     |
     v  POST http://localhost:9001/mcp  (JSON-RPC 2.0)
[server/server.py :9001]  -->  workspace/ (real file writes)
     |
POST /sessions/{id}/close
     |
     v
TRACE claim (Ed25519 signed)  -->  workspace/trace-claim.json
     |
     v
cmcp_verify.verify_trace_claim()  (no network, no operator trust)