send_session_message

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

With no annotations, the description carries the full burden, and it does disclose the key behavioral choice: synchronous await vs. asynchronous dispatch into an inbox queue. It omits other important traits — what happens if the target session doesn't exist or is terminated, whether delivery is guaranteed, and what the awaited call actually returns.

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 tight sentences with the core action front-loaded and the delivery-mode caveat following immediately. No filler, though 'in the mesh' is slightly vague and the sentence could name the alternative tools it competes with.

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 5-parameter messaging tool with no output schema, the definition covers the action and delivery mode but not the return shape (what an awaited response contains) or failure conditions. Adequate to attempt a call, incomplete for predicting its outcome.

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 description coverage is 100%, so the baseline is 3; the schema already documents content, message_type, await_response, sender_session_id, and target_session_id. The description adds only a restatement of the async/await flag and nothing about the semantics of message_type values or sender defaults.

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?

States a specific verb and resource ('Send an instruction or follow-up message to a specific agent session'), which is clear on its own. However, it never distinguishes itself from close siblings like send_agent_message or broadcast_session_message, leaving the agent to infer the difference from names alone.

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 second sentence implies two modes of use (async into an inbox vs. awaiting the result) and loosely gestures at check_inbox/wait_for_inbox territory, but it gives no explicit when-to-use/when-not or named alternatives. Anything beyond 'you can do it synchronously or not' is left to inference.

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