Send Messages

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

With no annotations provided, the description carries the burden of disclosing behavior. It mentions message limits, required fields, and optional groupId, but does not describe delivery guarantees, error behavior, authentication requirements, or response format. For a mutating operation, this is only partial transparency, though the limits are a useful addition.

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 concise and well-structured, with each sentence adding necessary detail: purpose, structure, required/optional fields, and limits. It is immediately front-loaded with the core purpose and contains no redundant information.

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 tool with no output schema and no annotations, the description covers input structure, required parameters, optional group reply, and hard limits. It lacks details on return values or error semantics, but for a send action this is acceptable. The description is nearly complete for practical invocation.

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 input schema is empty, so the description is the sole source of parameter information. It explicitly lists required fields (appId, contactId, message, messenger), provides allowed enum values for messenger (signal/simplex/session), and notes an optional groupId for group replies. This fully compensates for the missing schema.

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 identifies the action ('Send one or more messages through PrivacyFlow') with a specific verb and resource. It distinguishes itself from sibling tools (check_health, verify_api_key, list_apps, poll_messages) which are all non-messaging operations.

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 provides clear context for when to use the tool (sending messages) and details optional group usage. It does not explicitly state when not to use or point to alternatives, but the sibling tools are clearly distinct, making usage obvious. The constraints (max 50 messages, 10,000 chars) also inform practical usage.

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