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

With no annotations, the description carries the full burden, and it does disclose genuinely useful behavior: the receipt is timestamped, independently verifiable, and checkable without an account. It does not say whether issuing requires auth, whether receipts are immutable or expire, or what the caller receives back (an ID, a URL, a signed blob).

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 sentences, zero filler, and the what (verifiable timestamped receipt) is front-loaded before the when. Every clause carries information an agent can act on.

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?

The tool is simple (2 params, no nesting, no annotations), but there is no output schema and the description never indicates the shape of the returned receipt or how a third party would consume it. For a tool whose entire value is the artifact it produces, that is a meaningful gap.

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 description coverage is 100%, so both `subject` and `detail` are already documented in the schema, and the description adds no syntax, format, or granularity guidance for them. The phrase "proving a task ran" loosely maps to `subject`, but that is the baseline level of value when the schema does the work.

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 artifact — a verifiable, timestamped receipt proving a task ran — with the key property that a third party can check it without an account. That is far more than a restatement of the name. It stops short of 5 because it never positions itself against the closest sibling, save_agent_checkpoint, which also records that something happened.

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?

"Use this when your user asks whether something actually happened and you need evidence rather than a claim" gives a concrete triggering scenario and implicitly contrasts evidence vs. assertion. There is no explicit when-not guidance or named alternative (e.g., save_agent_checkpoint for internal state), so it is clear context rather than full routing.

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