send_to_session

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

No annotations exist, so the description carries the full burden. It usefully discloses that the tab is reused (no new resource created) and that a session must pre-exist, but says nothing about what happens if the session name is unknown, whether the call is blocking, or how output is obtained (a sibling get_command_output exists).

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 short sentences, front-loaded with the action, then the preference rule, then the prerequisite. No filler; every sentence changes agent behavior.

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?

A simple two-parameter tool with a fully documented schema and no output schema; the description covers selection and prerequisite context adequately. The main residual gap is output retrieval guidance for a command-sending tool.

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 both parameters are already documented in the schema; baseline 3 applies. The description adds only that session_name must refer to an existing named session, with no details on name matching or command syntax.

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+resource: send a command to an existing named terminal session, and clarifies it reuses the session's tab rather than creating one. This distinguishes it from open_terminal_tab, though other execution siblings (execute_command, execute_with_streaming, wave_run_in_block) are never named as contrasts.

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?

Explicit positive guidance ('Always prefer this over opening a new tab when a relevant session already exists') plus a concrete prerequisite step ('Use list_sessions first to check for available sessions'). The when-to-use condition and the alternative are both spelled out.

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