list_messages

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

With no annotations present, the description must carry the safety/behavioral burden. It explicitly discloses that the operation is read-only and uses GET, which rules out side effects. It does not mention pagination, authentication, or response shape, but for a simple list operation this is reasonably transparent.

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 deliver the operation, endpoint, side-effect profile, and a tool-ecosystem note with no redundancy. The essential action is front-loaded.

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 low-complexity tool with a single integer parameter and no output schema, the description provides enough context to call it correctly. It could be more complete by mentioning what the response contains or how messages are ordered, but that is not critical.

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 0%, so the description needs to clarify the conversationId parameter. The endpoint path /v1/conversations/{id}/messages maps {id} to conversationId and explains that it is the conversation/thread identifier, adding meaning beyond the bare integer schema.

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 action ('List messages in a thread') with an explicit endpoint, making the tool's purpose unambiguous and distinct from sibling listing tools like list_conversations. The read-only note reinforces that it is a retrieval operation.

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 clearly establishes when to use the tool: to read the messages of a specific conversation/thread. 'Read-only. There is no send tool' provides context and a limitation, though it does not name alternative sibling tools or explicitly state when to prefer them.

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