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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and external scope are covered. The description adds genuinely useful detail about returned fields (hash, UTC day), but leaves "recent" undefined and says nothing about default page size, ordering, or what happens when an agent has no receipts.

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 tight sentences with no filler; the return-content detail comes first and the sibling routing second. Nothing is repeated from the name or 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 no output schema, the description usefully sketches the return shape (hash plus UTC day), which is the right call. However, for a two-parameter tool with zero schema description coverage, it omits the semantics of both the agent identifier and limit, leaving an agent to guess on invocation.

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 0%, so the description must carry the parameter burden, and it largely does not. "of a demo agent" hints at the agent parameter but never states its expected format (ID vs. name vs. slug), and the limit parameter — including its 1-100 range and default — is never mentioned.

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 the concrete resource (decision receipts) and the scope (recent, per demo agent), and states what each item carries: SHA-256 hash and UTC day. It also names the sibling verify_receipt, so an agent can separate listing from verification without opening a 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?

"Verify any of them with verify_receipt" gives an explicit routing rule to the correct sibling for the natural follow-up action. It stops short of saying when to prefer this over list_agents or when not to use it, but the core use/alternative split is clear.

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