Update a SIP trunk

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

Annotations already indicate readOnlyHint=false and destructiveHint=false, and the description does not contradict them. It adds valuable behavioral detail beyond annotations: the PATCH-like behavior ('Only the fields you send are changed') and the required scope (`sip_trunks:write`), which helps the agent understand auth preconditions and non-destructive partial updates. It does not disclose response behavior, but this is not a contradiction and annotations reduce the burden.

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?

Two short sentences carry the essential information: what the tool does, its update semantics, and its auth requirement. Every sentence earns its place, and the core verb-resource meaning is front-loaded. No wasted 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?

For a 12-parameter mutation tool with no output schema, the description is minimally viable but not rich. It states scope and partial-update semantics, but omits what the caller should expect in return, how errors are surfaced, or any explicit relationship to sibling tools such as get_sip_trunk for resolving ids. The basics are covered, yet an agent would benefit from more operational context.

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 schema covers about 75% of parameters with descriptions, and the description adds a key general semantic: sending only specific fields leaves others unchanged. However, it does not compensate for the three undocumented parameters (username, transport, auth_realm), nor does it add per-parameter meaning beyond the schema. The partial-update sentence is useful, but parameter guidance remains mostly delegated to 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?

Description opens with a clear verb and resource: 'Change a SIP trunk.' It also specifies the update semantics ('Only the fields you send are changed'), which unambiguously distinguishes it from create_sip_trunk, delete_sip_trunk, and get_sip_trunk. The purpose is immediately obvious.

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?

No explicit guidance is given about when to use this tool instead of alternatives. It never mentions create_sip_trunk for new trunks, delete_sip_trunk for removals, or get_sip_trunk for reading. The context is implied by the verb 'Change,' but exclusions and alternative routes are absent.

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