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

Annotations already declare readOnlyHint=true and openWorldHint=false, so the safety profile is covered. The description adds useful return-side context — ordering (newest first), the nature of the entries, and that each carries a source URL — but says nothing about pagination behavior, result caps, or data freshness.

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 dense sentence that front-loads the resource and ordering. Every clause (verified, banked grants, newest first, source URL) carries information, though the parenthetical could be trimmed.

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 does the work of sketching what a record contains (dated, verified resets, grants, source URL, ordering). Combined with a fully documented input schema, an agent has enough to call it correctly, though the lack of any usage routing leaves a small 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 description coverage is 100% with defaults, ranges, and enums all documented in the schema itself, so the baseline is 3. The description adds no parameter guidance; the parenthetical '(group credits)' only loosely gestures at the 'credits' enum value already listed in the schema.

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 names a specific resource ('Codex reset history') and details its contents: dated verified usage-limit resets and banked reset grants, ordered newest first, each with a source URL. It is clearly a retrospective record, which implicitly separates it from get_reset_forecast, but it never names or contrasts with that sibling explicitly.

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?

There is no when-to-use statement, no exclusion, and no pointer to the alternative tools. An agent must infer from the word 'history' that this is for retrospective lookup rather than forward-looking forecasting, which get_reset_forecast presumably handles.

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