send_message_fast

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

No annotations are provided, so the description carries the full burden. It discloses the key behavioral trait (skipping the typing indicator) but omits other relevant details like authentication requirements, side effects, or response format. Since it is a send operation, the mutation nature is implied but not stated. The description adds some behavioral context but is not comprehensive for a write operation.

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 with no wasted words. The key differentiator (skipping the typing indicator) is front-loaded, and the usage condition follows immediately. This is a model of conciseness.

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?

The description gives the essential differentiator and usage condition, but given the absence of annotations and an output schema, it leaves out return value details and potential error conditions. It also does not mention the optional device_id requirement unless the environment variable is set, though the schema covers that. For a variant tool, it is adequate but not fully complete.

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?

The description does not add any parameter-specific meaning. However, schema coverage is 100% (all four parameters have descriptions), so the schema already explains the parameters. The description's reference to 'Same as send_message' implies the same parameters, but it does not elaborate. Baseline 3 is appropriate because the schema handles parameter documentation.

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 says 'Same as send_message but skips the typing indicator,' which implies it sends a message and clearly distinguishes it from the sibling. It does not explicitly state the verb and resource ('send a message') but relies on the sibling for context, which is acceptable given the close relationship. The purpose is clear for an agent that knows send_message.

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?

Explicitly states when to use: 'Use for time-sensitive messages such as OTP.' It also names the alternative 'send_message' implicitly through 'Same as send_message,' so the agent knows the default option. This is clear guidance without ambiguity.

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