Create a SIP trunk

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

Beyond the annotations, the description discloses important behavioral outcomes: the returned platform_ip and origination_uri must be used for allowlisting and origination setup. It also states the required scope. This adds meaningful post-creation context and authentication expectations that the annotations do not convey.

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?

Every sentence contributes: the core function, a key boundary (no resale), critical follow-up steps, and required scope. It is compact and front-loaded with the primary purpose.

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 an 11-parameter tool with no output schema, the description provides essential context about the returned values and next steps, plus scope requirement. It does not explain parameter interactions like send_plus or dial_prefix, but those are adequately documented in the schema. Overall it is sufficient for an agent to invoke the tool and continue the workflow correctly.

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 73%, so the schema already documents most parameters individually. The tool description adds no direct parameter-level guidance, but it gives contextual framing around carrier setup (allowlist, origination URI). It does not compensate for the three undocumented parameters (transport, username, auth_realm) but is not required to do so at this coverage level.

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 (connect) with a clear resource (user's own carrier) and names the operational outcome. It distinguishes itself from sibling operations like checking status or updating by describing the creation workflow, and the title reinforces the action.

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?

It clearly states when this tool is used: when the user brings their own carrier, and explicitly notes Wixzel does not resell telephony. It also gives a follow-up instruction to run check_sip_trunk_status. It does not explicitly name alternative tools or exclusion conditions, but the context is unambiguous.

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