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

The description adds useful behavioral context beyond a bare endpoint: it mentions durable rows from pbx-index, derived ext_NNN identities from Transfer edges, scoping by x-temsor-pbx-key, and privacy/cost hints like 'KVKK forget ready' and 'Idle $0'. However, it omits pagination behavior, response shape, and error or edge-case details, which matter because no annotations exist.

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 mixes a product slogan ('Light CRM from call graph / facts'), endpoint syntax, implementation details, and business statements like 'No DID sales' and 'Advanced: own PBX/Asterisk stays on customer.' The key invocation information is buried and the phrasing is telegraphic, so the structure does not support quick comprehension.

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?

With no output schema and no annotations, the description carries the full burden of explaining what the agent will receive. It does not describe the response structure, field names, count behavior, or pagination, and it fails to mention include_extensions as a parameter. The data-source and scoping details are useful but not sufficient for a complete call decision.

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 coverage is 100%, so the schema already documents all parameters well. The description's inline endpoint restates q, kind, limit, and call_id without adding meaning beyond the schema, and it omits include_extensions entirely. This does not exceed the baseline expected when schema descriptions are complete.

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 identifies the resource as PBX persons and communicates that it returns caller phone/name data plus derived extension identities. It is more specific than a tautology but does not explicitly differentiate itself from the sibling pbx_persons_get, so it stops short of a 5.

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 offers no direct guidance on when to use this tool instead of alternatives such as pbx_calls, pbx_facts, pbx_persons_get, or pbx_search. There is no 'use this when...' or 'for X use...' statement, leaving the agent to infer the intended use from the endpoint.

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