send_message

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It reveals two critical constraints: messages cannot be recalled and new conversations cannot be initiated. This adds meaningful context beyond the schema, though it does not mention error states, authentication, or rate limits.

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?

Three sentences, each earning its place: the first states the core action, the second explains the existential constraint, and the third notes irreversibility. No filler or redundant phrasing; the structure is front-loaded with the primary purpose.

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 simple tool with two parameters and no output schema, the description covers the essential operational context: what it does, the prerequisite for existing conversations, and the irreversible nature of sending. It omits potential error handling or side effects, but these are not critical given the tool's simplicity and the complete parameter coverage.

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 schema already offers 100% parameter coverage with concise descriptions for both text and chat_guid. The description adds value by reinforcing that chat_guid must come from list_chats and be an existing conversation, giving the agent a clearer semantic understanding of the parameter's provenance and validity.

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 'Send a message to an existing conversation,' clearly identifying the verb (send), resource (message), and scope (existing conversation). This distinguishes it from sibling read-only tools like get_messages and search_messages, which focus on retrieval.

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?

It explicitly states that only existing conversations can be addressed and that there is no way to start a new conversation, providing clear when-to-use and when-not-to-use guidance. It also references list_chats as the source for chat_guid, implying the correct workflow, though it does not explicitly contrast with alternative send-related tools (none exist).

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