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

The annotations already establish that this is a read-only, open-world operation. The description adds real behavioral context beyond them: it states that a paid API key is required, which is an authentication prerequisite the agent must plan for, and it explains that passing tx_hash and proof bypasses the server's own index, which is a trust-model detail the agent could not infer from the schema or annotations.

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?

Two short sentences, with the core purpose and the authentication requirement front-loaded, followed by the optional-parameter optimization. No filler or repetition of the title.

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?

With only three parameters, full schema coverage, and read-only behavior already covered by annotations, the definition covers what an agent needs before calling the tool. Since there is no output schema, the description does partial duty by indicating the result includes who anchored the hash and when, though it does not explain the shape of a failed or unverified result.

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?

Schema coverage is 100%, so the baseline is 3. The description nonetheless adds meaning beyond the schema by framing both optional parameters as coming from a receipt and by stating the consequence of supplying them (chain-only verification). That is semantic value the schema field descriptions do not convey.

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 names a specific verb and resource: it checks a hash's anchoring against the blockchain and returns who anchored it and when. This is clearly distinct from the sibling tools (anchor_hashes, anchor_hash_text), which create anchors rather than verify them, so the agent can tell them apart without consulting the schema.

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?

The description implies when to use the tool: to confirm a prior anchor. It also adds a useful usage condition, that supplying tx_hash and proof from a receipt makes the check depend only on chain data. However, it never states when to use this tool instead of anchor_status, which a sibling whose purpose could overlap. That guidance is left to inference.

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