Send Session Message

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

No annotations are provided, so the description carries the full burden. It does not say whether the call blocks until the session responds, whether it mutates session state, what happens to a session that is paused or completed, or how the prompt/message fields differ. For a mutation-style tool with zero annotation coverage this is a substantial gap.

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?

A single front-loaded sentence with no filler. It is efficient, though the brevity reflects under-specification rather than disciplined compression.

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?

An output schema exists, so return values need not be explained, but with 4 parameters at 0% coverage, a confusing prompt-vs-message duplication, and no annotations, the definition is far too thin for an agent to invoke it confidently.

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 0% across four parameters, yet the description only obliquely gestures at 'prompt' via 'user message (prompt)'. It never explains the relationship between the separate 'prompt' and 'message' string fields or what '_meta' is for, leaving two ambiguous overlapping inputs undocumented in both schema and description.

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 a user message to an existing session'), which clearly separates it from the session CRUD siblings. It stops short of naming any sibling or the alternative path explicitly, so it doesn't reach the 5 bar.

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?

No when-to-use guidance, no prerequisites (does the session need to be active? in a specific state?), and no mention of alternatives among the eleven sibling tools. The 'existing session' phrasing hints at a precondition but never defines it.

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