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

Annotations already declare idempotentHint=true and destructiveHint=false, so the description doesn't need to restate those. The description adds the 'durable' and 'MCP task-compatible facade' context, which is useful. It does not disclose what happens to the underlying job, whether cancellation is graceful or forceful, or whether it is safe to call on a completed job, but the idempotent hint partially covers that.

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?

A single sentence that is front-loaded with the action and resource, and includes the key distinguishing qualifier ('MCP task-compatible facade'). No wasted words.

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-parameter cancellation tool with idempotentHint=true, the description is mostly sufficient. However, with no output schema and no explicit statement of what the response contains or what state the job transitions to, an agent has to infer the result. The sibling set includes ata_cancel_research_job and ata_cancel_research_workflow, so a bit more differentiation would improve completeness.

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%, so the schema already documents taskId as the MCP task id / durable jobId. The description adds no additional parameter meaning 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?

The description states a specific verb ('Cancel') and resource ('durable ATA research job'), and adds the qualifier 'through the MCP task-compatible facade' to distinguish it from the raw job-cancellation siblings. It is clear what the tool does, though it doesn't explicitly name the sibling it differs from.

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 description implies this is the MCP-facade variant for cancelling ATA research jobs, which hints at when to use it versus ata_cancel_research_job or ata_cancel_research_workflow. However, it does not explicitly state when to prefer this tool over those alternatives or mention any prerequisites (e.g., job must be running).

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