Interrupt a Codex turn

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

Annotations already mark destructiveHint=true and readOnlyHint=false, so the description carries a lower burden. It adds the useful condition that the turn must be still running, but it does not disclose side effects such as whether partial output is lost or whether the thread remains usable after interruption.

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 redundant content. It conveys the action, target, and condition in twelve words, making it highly efficient and easy to parse.

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 two-parameter tool with full schema coverage and annotations covering the destructive and idempotent nature, the description captures the core action and the key condition (still running). It lacks only minor detail about post-interruption behavior, which is not essential for correct invocation.

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%, and both parameters have clear descriptions in the schema (turnId is reported by send_to_codex_thread, threadId is the Codex thread id). The description adds no additional parameter-level meaning, so the baseline of 3 is appropriate.

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 ('Stop') and resource ('a turn ... in a Codex thread'), clearly distinguishing it from sibling tools that operate on threads or the app server. The qualifying phrase 'still running' further narrows the scope and makes the purpose unambiguous.

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 phrase 'still running' implies the intended use case—interrupting an active turn—but the description provides no explicit guidance on when not to use it or how it relates to alternatives like stop_codex_app_server. No when-to-use or when-not-to-use conditions are stated.

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