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

With no annotations, the description carries the full burden, and it does disclose the shape of returned items (model, tokens, USD cost, provenance), which is genuine behavioral content. But it omits what 'recent' means (time window), auth requirements, ordering, and any rate-limit context.

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?

Compact and front-loaded: purpose first, then a terse Args list. No filler, though the parenthetical field list and args sentence could be split for readability.

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?

There is no output schema, so the description must (and does) sketch the returned fields, and it documents the undocumented limit default/max. However, it lacks the when-to-use routing and the freshness semantics ('recent') an agent needs for a cost-reporting tool with several overlapping siblings.

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 only 50% (limit has no schema description), and the description compensates by stating limit's default of 25 and max of 100, which are not present in the schema. provider is only echoed from the schema's own example, so the gain is partial but real.

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+resource: returns itemized per-request costs for a provider, and lists the fields returned (model, tokens, cost, provenance). This distinguishes it from siblings like get_cost_accuracy and get_overview, though it never names an alternative 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?

No guidance on when to use this versus get_cost_accuracy, get_overview, or get_provider. It only lists args, leaving the choice of tool entirely to inference.

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