Timestamp a SHA-256 and get a receipt. Free, no account. Only the digest is stored — the document never reaches this server and cannot. The receipt states plainly what it proves now (the operator's timestamp) and what it proves after the next seal (anyone can check it without trusting the operator). Same digest, same receipt.
| Name | Required | Description | Default |
|---|---|---|---|
| sha256 | Yes | 64 hex characters — a sha256 digest. Other names accepted: hash, digest. |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Despite minimal annotations, the description richly discloses behavior beyond readOnlyHint=false: it is free with no account, only the digest is stored, the document never reaches the server, and the receipt's proof semantics change after the next seal. It also implies idempotence with 'Same digest, same receipt.'
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The core action is front-loaded in the first sentence, and every following sentence adds distinct value: cost/account model, privacy guarantee, proof semantics, and idempotence. There is no filler.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a one-parameter tool with no output schema, the description covers the essential behavioral context: what is stored, why it is private, and what the receipt proves over time. It could be slightly more complete by routing the agent away from sibling verification/seal tools, but it is otherwise sufficient to call correctly.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema has 100% description coverage for the single sha256 parameter, so the schema already documents format and aliases. The description adds no syntax or format details beyond what the schema provides, making 3 the appropriate baseline.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific verb and resource: 'Timestamp a SHA-256 and get a receipt.' That is clear enough to distinguish it from generic tools, but it does not explicitly differentiate from siblings such as project100_seal, project100_seal_proof, or project100_verify, which are likely adjacent operations.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It gives useful context ('Free, no account') but no explicit guidance on when to use this tool versus alternatives like verify or seal. The agent must infer the usage context from the action alone.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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