codex_select_task

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

With no annotations, the description must carry the behavioral burden, and it does disclose a meaningful stateful effect: subsequent messages go into the selected task. However, it says nothing about whether the selection persists across sessions, what happens with an out-of-range number, or what a successful call returns.

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 short sentences, zero filler, with the action and the follow-on state effect front-loaded before the invocation constraint. Nothing needs trimming.

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 single-integer selector with no output schema and no annotations, the description covers the essential semantics: what it selects, where the number comes from, and what happens after. Only error/edge-case behavior is left unstated, which is a minor gap.

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 coverage is 0% (schema only says integer >= 1), so the description must add meaning. It does: the number refers to the index from the just-listed task set, which is the key semantic the bare schema lacks. It could still clarify whether numbering is 1-based and stable after listing, so not a 5.

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 (select) and resource (Codex chat task) plus the selection key (the number just listed). It implicitly ties to the preceding listing rather than naming a sibling like codex_list_tasks, so it is clear but not fully differentiated from siblings by name.

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?

Gives a clear invocation condition: only call with the number the user explicitly specified, and notes it must follow a listed set of numbers. It does not explicitly name codex_list_tasks or state what to do if no list exists, so it stops short of full when/when-not guidance.

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