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

With no annotations, the description carries the full burden and does well: it discloses the auth requirement (platform staff, account session), the data surface (provider, mode, capacity, live health, telco warning, active calls), and a security guarantee ('Never returns secrets'). It omits pagination/rate-limit behavior, which is a minor gap.

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?

Three short sentences, each earning its place: audience/scope first, then the returned fields, then the filter semantic, closing with the secrecy guarantee. Zero 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 and no annotations, the description usefully enumerates what comes back and who may call it. The only real omission is pagination semantics for limit/offset, which an agent would otherwise have to infer.

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 0% across 4 parameters, so the description must compensate. It explains `problems` precisely and `provider` implicitly as both a filter and a returned field, but limit/offset are left entirely undocumented beyond their conventional meaning.

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?

Specific verb+resource (lists phone lines) with scope ('across workspaces') and privileged audience ('Platform staff only'). The cross-workspace framing cleanly distinguishes it from the sibling lines_list, which is workspace-scoped.

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?

Gives an explicit usage rule for the `problems` filter ('lists only lines that are unhealthy or have a warning') and states the access context (platform staff, account session). It does not explicitly name lines_list as the workspace-scoped alternative, so the routing is implied rather than spelled out.

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