List SIP credentials

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

Annotations already indicate readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds value by noting the exclusion of HA1 and password, inclusion of live counts, and listing possible errors. 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?

Two sentences plus error list: the first sentence states purpose and key details, the second provides usage guidance, and errors are listed concisely. No unnecessary words, effectively front-loaded.

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?

Given the simple input (one parameter), no output schema, and many sibling tools, the description is complete. It explains what is returned, what is omitted, how to get the input, and potential errors. No gaps for an agent to select and invoke 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?

There is only one parameter (trunk_id) with full schema coverage (100%). The description adds meaning beyond the schema by stating 'Trunk group UUID (find it with trunk_list)', guiding the user to obtain the value. No other parameters require elaboration.

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 explicitly states 'List SIP Digest credentials for an owned trunk (no HA1, no password), each enriched with live registration_count and active_call_count.' This provides a specific verb and resource, clearly distinguishing from sibling tools like trunk_list_credential_calls and trunk_list_credential_registrations.

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 instructs to 'Use trunk_list first to find the trunk id' and lists specific errors (INVALID_ID, NO_ACTIVE_CUSTOMER, TRUNK_UNOWNED, INTERNAL_ERROR). It provides clear context for use, though it does not explicitly exclude alternatives or state when not to use.

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