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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the mutating nature is covered; the description adds real value by bounding the blast radius ('No payment or trade effects'), which tells the agent no funds or positions are at risk. It does not state whether cancellation is reversible, idempotent, or what happens when the state check fails. Note the phrase 'read-only ... task' describes the task type, not the cancel operation, so it does not contradict readOnlyHint=false.

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 constraints front-loaded and the blast-radius caveat second; no filler, no restatement of the tool name.

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 destructive single-parameter mutation with no output schema, the definition covers ownership, state, and financial scope but omits the outcome: success signal, error behavior for already-completed tasks, and any confirmation/idempotency semantics. Adequate to attempt the call, incomplete for handling its edge cases.

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?

There is one parameter with 0% schema description coverage, so the description must carry the burden. It adds ownership semantics ('your own') to taskId, but never explains that the lone argument is the task identifier or how to obtain it. The schema's uuid format and pattern partly self-document the type, keeping this at a minimal 3.

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 gives a specific verb and resource ('Cancel ... customer research task') plus three scope constraints: ownership ('your own'), lifecycle state ('queued or running'), and task type ('read-only customer research'). It does not name or contrast with any sibling such as create_research_task or get_task_result, so it lands at clear-but-undifferentiated rather than a full 5.

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?

Preconditions for use are stated inline: the task must be the caller's own and must still be queued or running, which implicitly excludes completed/failed tasks and other users' tasks. It stops short of naming an alternative tool or telling the agent what to do if the task is already finished.

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