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

With no annotations, the description carries the full burden. It adds real context about response character ('personality based on what the camera has seen', awareness of camera presence), but says nothing about whether the exchange is stateful/conversational, what happens with an unknown slug, or whether the call is read-only vs. affecting state.

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 tight sentences with the core action front-loaded and the roster pointer placed early. No filler, though the personality sentence could be trimmed without losing calling information.

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 3-parameter, no-annotation, no-output-schema tool, the description covers the main interaction but omits the `name` parameter's purpose and the relationship to the very similar talk_to_trout sibling — leaving an agent with a real ambiguity to resolve on its own.

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 only 33%; the description compensates partially by explaining where valid `fish` values come from (pool_roster) and that it must be a named pool regular. The optional `name` parameter and the `message` parameter are left entirely undocumented in both schema and description.

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 ('Chat with a named wild trout from the pool') and deictically points to pool_roster for valid names. However, the sibling talk_to_trout is never distinguished, so an agent cannot confidently tell which chat tool is intended.

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 '(see pool_roster)' pointer gives an implied prerequisite step for obtaining a valid fish slug, but there is no explicit when-to-use/when-not guidance and no routing away from talk_to_trout or answer_trout_question.

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