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

Adds substantial context beyond the annotations: rate limits (one live application per gig, 5 per day), the prerequisite 'Allow my assistant to act' switch, and the key semantic that the fee is derived from the gig's listed budget with no fee input. This explains the destructiveHint/idempotentHint pairing in operational terms the agent needs.

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 compact sentences, front-loaded with the action and its source, followed by fee semantics, limits, and the prerequisite. No filler and no repetition of the schema.

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 an action tool with no output schema, the description covers origin of the id, side-effect semantics, quota limits, and the authorization switch — everything needed to invoke correctly. Nothing material is left for the agent to infer.

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 gig_id and note are already documented, warranting the baseline 3. The description adds real meaning on top by clarifying that no fee parameter exists and that the fee is sourced from the gig budget, heading off an agent attempt to pass a price.

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 ('apply') and resource ('open gig'), and pins the object's origin to search_open_gigs with a scope qualifier ('GigXchange member-posted gigs only'). An agent can distinguish this from make_offer and respond_to_booking without reading the 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?

Names the upstream tool that produces valid gig_ids (search_open_gigs) and states the prerequisite switch, giving clear context for when the call will succeed. It stops short of explicitly naming the adjacent alternatives (make_offer, respond_to_booking) and when-not to use them.

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