codex_capabilities

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

Given no annotations, the description carries full behavioral burden. It discloses that it runs no review, does not modify anything, may take a moment to probe connectors, and supports a configuration-only mode via the probeConnectors parameter.

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?

The description is compact yet information-dense. It opens with a clear statement of purpose, then covers usage, side effects, and a practical parameter tip—all in two short paragraphs with no 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 diagnostic tool with no output schema, the description adequately explains what will be reported (reachable evidence, forbidden actions, withheld tools) and the optional parameter's effect. It is complete for an agent to decide when and how to invoke it.

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?

Although the schema already describes the parameter with 100% coverage, the description adds meaningful nuance: the time trade-off of probing and the option to disable it for a faster configuration-only answer. This goes beyond the schema's static description.

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 states the tool reports what evidence it can reach and what it is forbidden to do, using a specific verb ('Report') and resource ('this codex-mcp instance'). It distinguishes itself from sibling tools like codex_qualify and codex_auth_status by focusing on capabilities and policy restrictions.

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?

Explicitly tells the agent when to use it: 'before you rely on it' to check availability of the requirement system or database and which tools were withheld. Also states it is diagnostic-only and changes nothing, setting expectations for use.

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