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. It only states the action without disclosing side effects, required session state (e.g., must be active), asynchronous behavior, or potential errors. This is a significant gap for a tool that mutates by sending a message.

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 concise sentences, no waste. The action is front-loaded, and the sessionId provenance is immediately relevant.

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 only two parameters and no output schema, the description covers the basic purpose and prerequisite. However, the lack of behavioral details (e.g., session must exist, possible errors) leaves it incomplete for an agent to safely invoke without assumptions.

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 provides no descriptions (0% coverage), so the description must compensate. It does clarify that sessionId is the one returned by create_workspace and that message is a 'prompt/instruction', adding some meaning. However, it stops short of explaining formats, constraints, or how the message is processed.

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 the action ('Send a prompt/instruction') and the target resource ('a coding agent session'). It also provides a critical pointer to the sessionId source, which distinguishes this from sibling tools like get_session_status or cancel_session.

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 gives clear context on the prerequisite: the sessionId must come from create_workspace. This implies the appropriate workflow but does not explicitly discuss when not to use this tool or compare it to alternatives like archive_workspace.

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