Precleared MCP Server

Verify receipt

verify_receipt

Read-onlyIdempotent

Retrieves a Precleared receipt by ID to show what was checked, when, the verdict, and the hashes, signature, and public key needed to verify proof for a person or audit.

Instructions

Fetch a Precleared receipt by its id (cc_rcpt_...) to show what was checked, when, and the verdict, with the hashes, Ed25519 signature and public key needed to verify it. Use it when a person or an audit asks for proof of a check.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "id": "<id>"
    },
    "name": "verify_receipt"
  }
}

Input Schema

Name	Required	Description	Default
`id`	Yes	Receipt id, such as cc_rcpt_0123456789ABCDEF.

Output Schema

Name	Required	Description
`id`	Yes	Receipt id.
`verdict`	No	Verdict given.
`algorithm`	No	Signature algorithm.
`signature`	No	Ed25519 signature, base64.
`confidence`	No	Confidence given.
`created_at`	No	When the check was made.
`public_key`	No	Public key, base64 SPKI DER.
`key_version`	No	Signing key version.
`request_hash`	No	SHA-256 of the request.
`response_hash`	No	SHA-256 of the response.
`rules_applied`	No	Rule keys used.
`rules_version`	No	Rule set version.
`sender_country`	No	Sender country.
`recipient_domain`	No	Recipient domain.
`recipient_email_masked`	No	Masked recipient address.

Schema Changelog

Changes observed during successful MCP inspections.

First observedv1.4.0Nov 11, 2026

TDQS

A4.2/5.0

Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already establish readOnlyHint and idempotentHint, so the safety profile is covered. The description adds real value beyond that by disclosing the returned verification material (hashes, Ed25519 signature, public key) and the fact that verification is done externally against those artifacts. It does not mention behavior when the id is unknown or a receipt is absent, which keeps it at 4.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two sentences, front-loaded with what is fetched and what comes back, followed by the usage trigger. No filler, no repetition of the title, and every clause carries information an agent would otherwise have to guess.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a single-parameter read tool with an output schema and annotations, this is close to complete: purpose, identifier format, usage trigger, and return contents are all present, and the output schema handles the return shape. The only gap is edge-case behavior (invalid or missing receipt id), which is minor but unstated.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 100% and the single `id` parameter already carries an example format, so the schema does the heavy lifting. The description only restates the id prefix, adding no new syntax, constraints, or lookup semantics. Baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb (fetch) and resource (a Precleared receipt) and even pins the identifier shape (cc_rcpt_...), so the agent knows exactly what object is being retrieved. It also enumerates the payload (what was checked, when, verdict, hashes, signature, public key), which makes the tool unmistakable and clearly distinct from the contact_check/suppress_contact siblings.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives an explicit triggering condition: 'Use it when a person or an audit asks for proof of a check.' That is clear context for when to reach for this tool. It stops short of stating when-not to use it or naming an alternative, so it falls just below the top mark.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Deploy Server