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

Annotations already declare destructiveHint=true, readOnlyHint=false and idempotentHint=false, so the mutation/repeatability profile is covered. The description adds useful context that a dry-run verification path exists, but says nothing about what the server creation entails, whether existing servers are affected, or permission requirements.

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 with zero filler, and the core purpose is front-loaded before the verification hint. Every clause earns its place.

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 7 parameters, 14% schema coverage, no output schema and no parameter documentation in the description, an agent has almost nothing to reason about for port, transport, or allowed_sip_ips. The description is too thin for the tool's complexity, even accounting for annotations that cover the safety profile.

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 only 14% (only organization_id is documented), and the description contributes no parameter meaning at all — port, transport, allowed_sip_ips and server_address are unexplained in both places. For a 7-parameter tool with one documented field, the description should compensate but does not.

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 states a specific verb and resource ('Create a customer phone server for self-hosted media/calling'), which clearly distinguishes it from list_phone_servers and identifies test_phone_server as the dry-run counterpart. It is clear and actionable, though the differentiation from the create-side siblings (create_agent, create_campaign) relies only on the resource noun.

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 mention that 'test_phone_server dry-run verifies it' implies a sensible pre-creation workflow, but the description never states when to use this tool versus the dry-run or when creation is appropriate. Usage is inferable rather than explicit, with no exclusions or prerequisites.

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