call_history

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

Annotations already communicate readOnlyHint, idempotentHint, and destructiveHint=false, so the safety profile is covered. The description adds that the result is paginated and that filters are optional, but it does not disclose ordering, response shape, rate limits, or authentication requirements. No contradiction with 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?

A single sentence with the verb front-loaded, the core resource named, and the optional filters summarized. Every word earns its place; no redundant or vague 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 simple read-only list operation, the description plus the detailed schema provide enough to select and invoke the tool correctly: required offset/limit are in the schema, optional filters are summarized, and annotations cover safety. The main missing context is the response shape and default behavior when no time range is provided, but that does not block correct invocation.

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 57%, and the description adds value by grouping filters (direction, time-range, number, connection) that map to directions, from/to, phone_number, and connection_ids. However, it does not clarify limit, offset, or the directions enum values, so it only partially compensates for missing schema descriptions.

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 and resource: 'List paginated call history', and enumerates the optional filter dimensions (direction, time-range, number, connection). This clearly identifies what the tool does and distinguishes it from siblings like send_sms, initiate_call, and list_users by its unique 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 intended use is implied by the phrase 'List paginated call history', so an agent can infer this is the read-only history lookup tool. However, there is no explicit guidance about when to use it versus alternatives, nor any exclusions or routing to sibling tools.

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