⚠️ Send message

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

Annotations already indicate destructiveHint=true and readOnlyHint=false. The description adds critical behavioral context: message is immediately and publicly visible, not automatically removed, can be deleted via messenger_delete_message, and requires user confirmation. No contradiction with annotations.

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 with 4 sentences. First sentence front-loads the core purpose. Subsequent sentences add essential warnings, requirements, and alternatives without redundancy. Every sentence 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?

Given the tool's simplicity (no output schema, 2 required params), the description is complete. It covers purpose, behavioral warnings, prerequisites, constraints, and alternatives. An agent has all necessary context to invoke the tool correctly.

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% and provides detailed descriptions. The description adds value by specifying the source of chat_id (from messenger_get_chats_v2) and reinforcing the visibility implication for text. While helpful, it largely reinforces schema info.

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 it sends a TEXT message to a chat on behalf of the account. It distinguishes from the sibling messenger_post_send_image_message by explicitly noting the alternative for images. The verb 'sends' and resource 'message' are specific and unambiguous.

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 explicit guidelines: warning about public visibility, requirement to confirm text with user, required parameters and their source (chat_id from messenger_get_chats_v2), text limit, and alternative for images. It effectively tells when to use and when not to use this tool.

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