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

With no annotations, the description carries the full burden, and it does disclose the important consequence: escrow is refunded and bid stakes are returned. It is silent on irreversibility, required permission scope (the schema hints at a 'jobs' scope api_key), and whether cancellation can be blocked by an active dispute.

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 short sentences with the action and its state scope front-loaded, followed by the consequence. Nothing is filler and no information is buried.

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 single-id mutation with no output schema and no annotations, the description covers the operation, its preconditions, and its side effects reasonably well. It stops short of the authorization and irreversibility details an agent might want before committing to a destructive call.

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% and both parameters carry inline descriptions, so the schema does the heavy lifting and 3 is the baseline. The description adds no format, constraint, or identifier detail beyond the schema — 'a job you posted' restates the ownership condition already implied by the schema note.

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 (cancels) and resource (job) with state scoping (open or awarded) and an actor (poster), which tells the agent this is the author-side cancellation path rather than a worker-side withdraw. It does not explicitly name the sibling it differs from (jobs_withdraw, jobs_dispute), but the scope makes the distinction readable.

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 'open or awarded' qualifier implies when this tool is valid, and the job_id schema note ('A job you posted') reinforces the ownership precondition. However, there is no explicit when-not guidance, no statement that non-cancellable states exist, and no named alternative for withdrawing a bid versus cancelling a job.

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