codex_status

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

No annotations are provided, so the description carries the behavioral disclosure burden. It states that this is a read operation and that it does not wait for completion, which is useful. It does not cover prerequisites, error conditions, or whether an active session is required, but the most important non-mutating, non-blocking traits are disclosed.

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 each add distinct value: what is read, how to use the optional threadId, and the non-blocking behavior. There is no wasted wording or repetition of schema 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 one-parameter read tool, the description covers the main invocation modes: all sessions or a specific thread. It also clarifies the non-waiting behavior. Since there is no output schema, a little more detail about the return shape would help, but the essential information for using the tool is present.

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 only defines threadId as an optional string. The description adds meaning by explaining that omitting threadId lists sessions, which implicitly defines the parameter's behavior. It doesn't explicitly say 'supply threadId to read one session,' but this is strongly implied by the structure.

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 identifies a read operation ('Read') and a specific resource: session state, pending questions, and the latest answer. This distinguishes it from action-oriented siblings like codex_start, codex_message, and codex_stop. The broader scope also differentiates it from codex_answer, so an agent can reliably understand what this tool is for.

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 gives one concrete usage rule: 'Omit threadId to list sessions.' However, it doesn't explicitly say when to prefer this tool over siblings like codex_answer or codex_events, nor does it name alternatives. The usage context is implied rather than fully stated.

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