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

With no annotations, the description carries the full burden and does disclose a key side effect: the other person is emailed, plus a caveat to only send user-requested content. It does not mention permissions, reversibility, or error behavior, but the email side effect is the critical disclosure.

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, front-loaded with the action and immediately followed by scope and side-effect caution. Every sentence earns its place with no filler.

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 two-parameter mutation with no annotations or output schema, the description covers the action, role scope, side effect, and id sourcing. Return values and failure modes are absent, but those are minor for this tool's complexity.

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 parameters are already documented (including the 2000-char limit). The description adds meaningful provenance for response_id by naming the tools that supply it, going beyond the schema's bare 'Id of the response'.

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+resource ('Send a private message in the conversation on a response') and clarifies it works for both buyer and seller roles, which cleanly separates it from siblings like respond_to_want or post_want.

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?

Gives clear context for use (posting into an existing response conversation) and explicitly routes the agent to get_responses or my_responses for the required response_id. No explicit when-not guidance, but the alternative sources for the id are named.

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