list_sessions

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

With no annotations, the description carries the full burden of behavioral disclosure. 'List' clearly implies a read-only operation, and the scope 'belonging to this API key' is useful, but the description does not mention pagination, response format, or any rate-limit or authentication considerations.

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, well-structured sentence that front-loads the core action and resource. Every word adds necessary meaning, and there is no redundancy or 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 zero-parameter listing tool with no output schema, the description is reasonably complete: it identifies the resource, the action, and the ownership scope. It does not describe the exact shape of the returned list, but 'List all sessions' sufficiently sets expectations for a simple enumeration.

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?

The tool has zero parameters, so there is nothing for the description to clarify beyond the schema. The baseline of 4 applies because no parameter documentation is needed; the description accurately reflects that the operation requires no inputs.

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 the specific verb 'List', the resource 'WhatsApp sessions', and the scope 'belonging to this API key'. This clearly differentiates it from sibling tools like create_session, get_session_status, and get_qr_code, which perform different actions on the same resource.

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 makes the tool's purpose obvious but does not explicitly mention when to prefer it over alternatives such as get_session_status. There is no exclusion guidance or comparison to sibling tools, so usage context is implied rather than stated.

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