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

Annotations already declare destructive, open-world, and non-idempotent behavior, so the description is credited for adding semantics beyond that: fields are 'recorded, never enforced,' no approval gate exists, and destination country is checked against workspace capabilities. It still omits practical consequences such as whether the call is actually dialed immediately or cost/quota implications.

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?

The description is a single front-loaded paragraph that leads with the action and then layers scoping facts. It is dense but every clause carries information; the parenthetical pointer to the purpose property is slightly redundant given the schema already holds the catalog.

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 a 15-parameter destructive mutation with nested runtime_config and no output schema, the description leaves too much unexplained – most parameters, the distinction from trial calls, and what the returned call object will contain. The behavioral notes it does include are useful, but they don't cover the tool's full complexity.

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 20% across 15 parameters, so the description must compensate and largely does not. It clarifies purpose, user_authorization, and recipient_type (and the purpose catalog actually lives in the schema, not here), but says nothing about to, policy, agent_id, categories, campaign_id, relationship, runtime_config, user_requested, organization_id, or agent_endpoint_id.

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 opens with a specific verb and resource ('Create an outbound call request') and adds scope ('A workspace that holds a number calls out'), which separates it from read/lookup siblings. It does not explicitly name adjacent siblings like create_trial_call, authorize_outbound, or evaluate_outbound_policy, though the 'no approval step' line implicitly distances it from the authorization tools.

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?

Usage is only implied: 'no approval step' hints that authorization isn't required first, and the country-capability line hints at a prerequisite check. There is no explicit statement of when to choose this over create_trial_call, authorize_outbound, or evaluate_outbound_policy, so the agent must infer routing.

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