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

With no annotations, the description carries the behavioral burden and discloses important behavior: scoping by x-temsor-pbx-key, found=false if missing, and a cost hint of Idle $0. It does not explicitly state read-only behavior or full response/error semantics, but the core behavior is covered.

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 very short and scannable, covering purpose, API path, scope, and missing behavior in a few lines. Some cryptic clauses like 'Idle $0' and 'No DID sales' may be confusing but do not add significant bloat.

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 one-parameter get operation with no output schema, the description is reasonably complete: it includes purpose, endpoint path, authentication scope, and missing-entity behavior. It lacks explicit response shape and alternative-selection guidance, but the tool's simplicity reduces the need for more.

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 only parameter, id, is already fully described in the schema as 'Fact id (e.g. fact_001)' with min/max length. The description merely confirms retrieval 'by id' and adds no meaningful parameter semantics beyond the schema.

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 'Get one extracted fact by id', which is a specific verb and resource. It distinguishes this from sibling tools like pbx_facts (likely listing facts) and pbx_calls_get by focusing on a single extracted fact via id.

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 indicates this is for retrieving one fact by id and notes 'found=false if missing', which helps the agent know when to use it. However, it does not explicitly contrast with pbx_facts or pbx_search, and phrases like 'No DID sales' are ambiguous.

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