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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), so the bar is lower; the description still adds real behavioral detail — pagination, case-insensitive partial-match search, the returned member fields, and the routing order (priority ascending, then weight descending). It stops short of things like rate limits or auth scopes.

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?

Dense and front-loaded: resource and scope lead, then search, pagination, and return shape. It is essentially one long run-on sentence, but each clause (routing order, member fields) carries useful information rather than padding.

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, the description carries the return-value burden and does so fully — it enumerates the group fields and member trunk fields and explains the ordering. Combined with annotations covering safety, an agent has everything needed to call and interpret this tool.

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 100% and all three parameters (name, page, page_size) are documented in the schema, so the baseline is 3. The description restates the name search semantics (case-insensitive, partial match) but adds no syntax or format detail 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?

States a specific verb (List) and resource (Voice IN Trunk Groups) and even defines the resource in a parenthetical ('failover / load-balancing groups of inbound voice trunks'), which cleanly separates it from siblings like list_trunks, list_sms_trunks, and list_capacity_groups.

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 conveys that this lists the authenticated customer's trunk groups with optional name search, so the general usage context is implied, but it never states when to prefer this over list_trunks, get_trunk, or the create/update/delete trunk-group siblings. No explicit alternatives or exclusions are given.

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