Start a discussion with Codex

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

Adds behavior annotations don't convey: it is asynchronous, returning discussionId and turnId immediately while output must be fetched via discussion_read. The adjective 'read-only' describes the Codex session but could be misread against readOnlyHint=false, since the call itself creates discussion state; that nuance is not spelled out, which keeps it below a 5.

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?

Four short sentences, front-loaded with the core action, followed by the ordering constraint and the return contract. Dense and free of filler; the only slight cost is that the workflow and return details are packed together without visual separation.

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?

With no output schema, the description usefully states the return shape and the read-back path, which is the key gap for an async tool. It omits practical limits (message size, cost/latency of a turn, lifecycle of the discussion) that an agent would benefit from, but the essential calling contract 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?

Schema coverage is 75%, with cwd, model and effort already documented in the schema; the description mostly echoes those (absolute cwd, model from models_list). It adds light selection guidance for model/effort but leaves the required 'message' parameter (question plus relevant context) with no schema description and only a brief mention here.

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 and resource ('Start an independent read-only Codex conversation') and immediately tells the agent how it differs from the reading sibling ('read output using discussion_read'). It is clear this opens a new discussion rather than continuing one (discussion_reply) without needing to open any schema.

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 an explicit prerequisite sequence ('Call models_list first, then select model and effort for the question complexity') and names the follow-up tool for retrieving results. It does not state when NOT to use it (e.g., when to continue an existing thread with discussion_reply instead), so it falls short of full alternative routing.

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