msg_list_threads

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

With no annotations provided, the description carries the full burden of behavioral disclosure. The verb 'List' implies a read-only operation, but nothing is disclosed about ordering, pagination, whether threads include messages, or any limitations. The description lacks context about the result set's nature or behavior.

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?

The description is a single, front-loaded sentence that states exactly what the tool does without any superfluous words. Every part of the sentence earns its place, achieving maximum conciseness.

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?

The tool is simple with two well-documented parameters, but there is no output schema and no annotations. The description does not specify the return format or any behavioral specifics (e.g., sorting, thread metadata fields). It is minimally complete for a simple list operation but leaves key contextual 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?

Both parameters (agent and limit) are fully described in the schema (100% coverage), so the baseline is 3. The description adds no additional meaning beyond what the schema provides; it does not explain parameter interactions or defaults.

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 uses a specific verb 'List' with resource 'conversation threads' and scope 'for an agent', clearly distinguishing it from sibling tools like msg_list_agents (lists agents) and msg_read_inbox (reads messages). The purpose is unambiguous and exactly matches the tool name.

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 implies usage for retrieving threads for a specific agent, but provides no explicit guidance on when to use this tool versus alternatives like msg_search or msg_read_inbox. No when-not-to-use or alternative scenarios are mentioned; the usage is implied by the tool's purpose.

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