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

With no annotations, the description carries the burden and does disclose real behavior: it is a mutation, it is gated ('opens stay blocked until this succeeds'), and it requires an API key. Undisclosed are permission requirements (presumably ownership), failure modes, and idempotency of repeated approvals.

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 sentences, zero waste, with the purpose front-loaded and the consequence ('opens stay blocked') placed where it drives behavior.

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 2-parameter mutation with full schema coverage, no output schema, and no annotations, the description covers purpose, precondition, consequence, and auth — enough to call it correctly. It could be slightly stronger by pointing at get_share_status to verify the 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 description coverage is 100% — grant_id and api_key are already explained in the schema, including auth header preferences. The description adds no parameter-level detail beyond that, 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?

Specific verb+resource: 'Approve an owned grant that was created with requires_approval' tells the agent exactly what state transition occurs and on which object. It doesn't explicitly name deny_share as the opposite path, but the precondition makes the pairing intuitively clear.

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 condition for use is explicit: only grants created with requires_approval need approval. No exclusion or alternative is spelled out (e.g., use deny_share instead when rejecting), but the triggering context is clear enough to route correctly.

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