CPA: chats for a period

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

Annotations already indicate read-only, non-destructive, idempotent, and open-world behavior. The description reinforces this by stating 'Read-only, spends no money' and adds a rate limit constraint. No contradictions exist between the description and annotations.

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 concise (three sentences) and front-loads the main purpose. Every sentence adds value: function, read-only nature, deprecation guidance, downstream usage, and rate limit. No unnecessary words.

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?

Given the tool has three parameters, is read-only, and has no output schema, the description provides sufficient context: purpose, usage guidance, behavioral traits, parameter hints, rate limits, and downstream tool connections. It covers all essential aspects for agent decision-making.

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?

All parameters have schema descriptions with format specs (RFC3339) and bounds. The description adds context about pagination and that actionId values are suitable for other tools, which helps agents understand parameter usage beyond schema. With 100% schema coverage, the description still adds value.

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 clearly states the tool returns a paginated list of target CPA chats filtered by start time. It distinguishes itself from the deprecated v1 version and mentions that returned actionId values are suitable for other tools like cpa_chat_by_action_id. The verb 'Returns' and specific resource 'target CPA chats' make the purpose explicit.

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 explicitly recommends preferring this method over the deprecated cpa_chats_by_time_v1, providing direct sibling differentiation. It also notes that the tool is read-only and does not spend money, guiding appropriate use cases. The rate limit of 40 requests/min is mentioned, helping agents plan usage.

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