aximur-mcp

MCP server for the AXIMUR verification API — verify a claim against source evidence and get SUPPORTED / UNSUPPORTED / UNCERTAIN with confidence, reasoning, and an audit trail.

Use it before an AI agent acts on a claim: spends money, publishes, submits a form, cites a source, or makes a decision.

When to use AXIMUR

• Your RAG pipeline generates answers from retrieved documents — verify that the answer is supported by the source before showing it to a user
• Your AI agent is about to spend money, submit a form, or publish content — check the claim against the evidence first
• You need a citation-checking step between LLM output and consequential action
• You need an audit trail showing what evidence was used and what verdict was returned

Install

Requires Node.js >= 20 and an AXIMUR API key.

npx -y aximur-mcp

Add to your MCP client config:

{
  "mcpServers": {
    "aximur": {
      "command": "npx",
      "args": ["-y", "aximur-mcp"],
      "env": {
        "AXIMUR_API_KEY": "your-key-here"
      }
    }
  }
}

Works in Claude Desktop, Cursor, VS Code, and any MCP-compatible client.

Tool: aximur_verify

Verify a claim against supplied grounding evidence.

Parameters:

| Parameter | Type | Required | Description | |-----------|------|----------|-------------| | claim | string | yes | The claim to verify. | | grounding_source | string | yes | The evidence the claim must be grounded in. | | context | string | no | Extra context for the API. |

Example input:

{
  "claim": "The refund window is 30 days.",
  "grounding_source": "Refunds are accepted within 30 days of purchase when the original receipt is provided."
}

Example output:

{
  "verdict": "SUPPORTED",
  "confidence": 0.94,
  "reasoning": "The claim accurately reflects the policy. The evidence states refunds are accepted within 30 days of purchase.",
  "audit_trail": {
    "request_id": "req_7f21a8c4",
    "model": "aximur-v1",
    "matched_source_excerpt": "within 30 days of purchase",
    "grounding_source_sha256": "d48a3b2e1f7c9d06a5b4e3f2c1d0a9b8e7f6c5d4a3b2e1f0d9c8b7a6e5f4d3c2",
    "evaluated_at": "2026-06-26T14:30:00.000Z"
  },
  "latency_ms": 842
}

API key

Get an AXIMUR API key at https://aximur.com — $49/mo through Stripe.

Direct purchase link: https://buy.stripe.com/7sY14gce24tMd7n7kp38400

The key is read from the AXIMUR_API_KEY environment variable and stays server-side. It is never logged or exposed to the model.

Missing API key

If AXIMUR_API_KEY is not set, the server prints an error on startup:

ERROR: AXIMUR_API_KEY environment variable is not set.
Get an API key at https://aximur.com — $49/mo through Stripe.
Direct purchase: https://buy.stripe.com/7sY14gce24tMd7n7kp38400
Set it with: export AXIMUR_API_KEY=your-key-here
Or add it to your MCP client config under env.AXIMUR_API_KEY.
Install instructions: https://www.npmjs.com/package/aximur-mcp

If you see this error, set the environment variable in your MCP client config as shown in the Install section above.

Pricing

$49/mo — cancel anytime. API key delivered within 24 hours of purchase.

License

MIT