agent_steer

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

With no annotations provided, the description carries the full burden. It discloses the key behavior: it injects a message into the active turn and returns delivery=idle without sending characters when idle. It could add more detail about side effects or error conditions, but the core behavioral traits are covered.

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 compact sentences in Japanese: the first states the purpose, the second adds the critical exclusions and idle behavior. No filler or redundant phrasing; each sentence carries essential information.

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 two-parameter tool with an output schema, the description covers purpose, usage constraints, and a specific return behavior (delivery=idle). It lacks details on session_id semantics and edge cases, but the core operational guidance is sufficient.

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 describes 'text' well (string to add to the current turn, UTF-8 max 64KiB), but 'session_id' is undocumented. The description's phrase 'additional message' aligns with 'text' but adds no new parameter-level meaning, and it does not compensate for the missing session_id documentation.

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 states a specific action: inserting an additional message into a running Codex/Grok agent to steer the current turn. It clearly distinguishes itself from starting an independent next turn, which separates it from launch/turn tools in the sibling list.

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 says when to use (while an agent is running, to steer the current turn) and when not to use (when idle or wanting to start a new turn). The idle behavior with 'delivery=idle' further clarifies the intended usage window.

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