Read background Codex job events

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

Annotations already declare readOnlyHint=true and destructiveHint=falsecars, so safety is covered. The description adds meaningful behavioral detail beyond that: it explains cursor-based pagination semantics and the incremental-read pattern ('Pass the returned next_cursor back as "since"'), which is valuable for correct use.

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 earning its place: the first states the core purpose, the second teaches cursor resumption, and the third explains filtering. No filler or redundancy.

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 read-only paginated log tool, the description covers what the agent needs: how to page, how to continue from a cursor, and how to filter. The annotations cover safety, and the schema covers parameters. The absence of an output schema is mitigated by mentioning JSONL events and next_cursor.

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 100%, so the baseline is 3. The description adds value by clarifying that 'since' is a cursor returned by a previous call and that 'types' can reduce noise, going slightly beyond the schema's bare definitions.

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 and resource: 'Page through the JSONL events of a background run.' This clearly positions the tool as an event-log reader and distinguishes it from siblings like codex_job_status and codex_job_cancel, which cover status and cancellation rather than raw event streams.

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 description provides concrete usage context: paginate with next_cursor, resume with 'since' for new data, and reduce volume via 'types'. It does not explicitly name alternatives or state when not to use the tool, but the event-log framing makes its intended role clear against the sibling tools.

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