Send message to phone

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

Annotations already provide destructiveHint and openWorldHint. The description adds context about creating temporary contacts and returning contact_was_new/contact_removed, which are side effects beyond annotations. However, it does not detail error cases or all behavioral nuances.

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 a reference link. Information is front-loaded: first sentence states the core purpose. Every word serves a purpose; no redundancy.

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 tool's complexity (8 parameters, output schema exists), the description covers the high-level flow and return values. It relies on the schema for parameter details, which is acceptable, but could briefly mention interaction between parameters like files and message.

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 coverage is 100%, so the schema documents all parameters thoroughly. The description provides overall flow context but does not add additional meaning to individual parameters beyond what the schema already offers.

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 clearly states the action ('Send') and the resource ('to a phone number'), and distinguishes it from siblings like 'send_message' by specifying the target is a phone number rather than a chat ID. It also mentions creating temporary contacts, which is specific.

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 implies usage for sending to phone numbers but does not explicitly compare with siblings or provide when-to-use vs when-not-to-use guidance. The link to full documentation exists but the description itself lacks direct usage guidelines.

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