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

Annotations only declare the generic safety profile; the description adds the real behavior: 10-minute TTL, single-hold constraint, named failure modes (too_many_holds, already_reserved) with the correct agent response for each, timer restart on re-call, and the fact that posting is never done on the user's behalf. The re-call/restart nuance is consistent with idempotentHint=true.

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?

Front-loads the action and timing, then sequences usage rule, return values, failure modes, and the no-auto-post constraint. Dense but every sentence carries operational information; 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?

With no output schema, the description still names the return payload (draft text and held_until), and it covers the error paths an agent must handle plus the cost ('Free'). For a one-parameter reservation tool this is complete enough to call correctly without further discovery.

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% and the single parameter already documents 'The draft's id from find_opportunities', so the description's mention of the same source is largely duplicative. Nothing about id format or sourcing is added 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 and resource ('Hold one draft from find_opportunities') plus scope: 10 minutes, connected user, one hold at a time. It is clearly distinguishable from siblings release_opportunity and submit_participation, which are named as the counterpart actions.

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 an explicit when ('user has PICKED a draft and is about to post') and an explicit when-not ('not to reserve work for later'). It also routes to alternatives by name: find_opportunities to get the draft, submit_participation or release_opportunity to clear an existing hold.

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