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

With no annotations present, the description carries the full burden and does so well: it discloses that a live network fetch is performed on the target URL (a side effect, not a pure cache read), that receipts are public-by-id so anyone holding the id can re-check, and that all returned strings are untrusted third-party data rather than instructions. These are exactly the auth/security/behavior facts an agent cannot infer from the schema.

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?

Three sentences, front-loaded with the core action and the fresh-recheck behavior before the usage and safety notes. Every clause carries information; there is no filler or restated boilerplate.

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 no annotations and no output schema, the description must explain both behavior and returns, and it covers what the result contains (a receipt plus a fresh recheck of the URL). It stops short of describing the shape of the receipt or recheck result, a minor gap given there is no output schema to lean on.

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?

There is a single parameter with 100% schema description coverage, which already documents receipt_id as the hex string returned by verify_write. The description restates that it comes from verify_write and adds that receipts are addressable by id, but adds no format or validation detail beyond the schema, so the baseline 3 applies.

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?

States a specific verb+resource ('Fetch a receipt') and immediately clarifies it bundles a second action ('plus a FRESH recheck: a new fetch of the target URL performed right now'). It explicitly ties the resource to its producer (verify_write) and differentiates itself from that sibling by emphasizing the stored-receipt retrieval plus live recheck.

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?

Gives two concrete triggering scenarios: propagation lag at first verification (CDN caches, eventual consistency) and an operator asking for proof of a past write. This is clear when-to-use guidance, but it never states a when-not or explicitly contrasts with the sibling verify_write for a first-time check.

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