cancel-message

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

With no annotations, the description has to carry the full behavioral burden, and it does disclose the most important quirk: a 404 is treated as success because the message already finished, which affects how the agent should interpret the result. It says nothing about idempotency on repeat calls, what happens to a partially generated message, or any auth requirements, so significant ground is left uncovered.

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 short sentences: purpose first, then the SDK mirror and endpoint, then the 404 quirk. Every sentence earns its place and nothing is padded.

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 simple two-parameter mutation with full schema coverage and no output schema, the description covers the essentials, including the non-obvious 404-as-success rule that would otherwise mislead an agent. The only real gap is the absence of any comparison with delete-message.

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 both chat_id and message_id are already documented, including that chat_id can be a UUID or numeric id. The description adds no parameter meaning beyond what the schema provides, which is the expected baseline when the schema does the heavy lifting.

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: cancel an in-flight assistant message generation, and pins it to a concrete endpoint. It's clear what the tool does, but it doesn't name the nearby sibling delete-message, so the boundary between canceling a generation and deleting a message is left for the agent to infer.

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 phrase 'in-flight assistant message generation' implies when to use it (while a generation is still running), but there is no explicit when-not guidance and no mention of the alternative, delete-message, which appears in the sibling list. Usage is implied rather than stated.

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