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

Annotations already declare readOnlyHint, idempotentHint, and non-destructive behavior, so the safety profile is covered. The description adds the important scoping constraint that results stay within the caller's household or participant/watcher scope, which is useful non-annotation context, but says nothing about result ordering, pagination beyond the limit parameter, or completeness of results.

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 sentences, no waste. The search action and its filter dimensions are front-loaded, followed by the scope constraint. Efficient and well-structured.

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 9-parameter search tool with no output schema, the description covers the main facets and the scope constraint but leaves gaps: no return shape information, no pagination behavior, and no explicit routing guidance among similar siblings. Adequate but with clear gaps.

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 description coverage is 56%, so roughly half the parameters are documented. The description adds the list of filterable dimensions (query, participant, status, intent, closeout outcome, activity date range) which maps to the parameters, but adds no syntax or format detail beyond what the schema already provides for the documented ones.

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 states a clear verb+resource ('Search coordination threads') and enumerates the filterable facets. It is distinguishable from sibling list_my_coordination_threads and get_coordination_thread, though it does not explicitly name those alternatives.

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?

Usage is implied by the filter enumeration and the scope note, but there is no explicit statement of when to use this tool versus list_my_coordination_threads, get_coordination_thread, or summarize_coordination_thread. The agent must infer the selection criteria.

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