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

Annotations already declare readOnly, idempotent, and non-destructive, so the safety profile is covered. The description adds real value beyond that: it discloses the cost ('Free'), that a decided request returns an Ed25519-signed receipt as a compact JWS, and that wait_seconds long-polls until a decision rather than returning immediately.

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 short clauses, front-loaded with the resource and its status set, then the return payload, then the optional blocking behavior. Every sentence carries distinct information and 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 two-parameter read tool with full annotation coverage and no output schema, the description covers purpose, possible states, return payload format, and long-poll semantics well. Minor gaps remain: it does not describe what happens on an unknown or expired-without-receipt id, or what a long-poll timeout yields.

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 both parameters are already documented in the schema, including approval_id's origin and the wait_seconds maximum. The description only reinforces that wait_seconds causes blocking until a decision; it adds no syntax, format, or edge-case detail (such as what a timeout returns) beyond the schema.

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 resource (an approval request) and its exact possible outcomes (pending | approved | denied | expired), so an agent knows precisely what it gets back. This is clearly distinguishable from request_approval (which creates one) and verify_receipt (which verifies a receipt), without needing to open any 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?

Usage is implied rather than stated: the status enumeration and the mention of the signed receipt suggest this is the polling/checking step after request_approval, and the 'Free' marker hints at cost considerations. However, it never explicitly says when to use this versus verify_receipt for receipt validation, nor when to skip it.

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