umbrella_api_usage_keys

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

There are no annotations, so the description carries the burden of explaining behavior. It does communicate the main behavior—returning usage broken down by API key—but it does not clarify response shape, read-only semantics, pagination, aggregation, or whether 'usage' means requests, responses, or something else.

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 brief and front-loaded with the key differentiator ('broken down by API key'). It wastes few words, though 'over a date range' somewhat repeats what the schema already communicates.

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 simple two-parameter reporting tool, the description conveys the core grouping dimension and required date range. However, with no output schema and no annotations, it leaves ambiguity about the exact usage metric and return format, which matters given the many similar umbrella usage 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 description coverage is 100%, so the from/to date parameters are already well documented. The description only rephrases 'date range' and adds no new parameter-level meaning such as date behavior, inclusivity, or timezone handling.

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 that the tool reports API usage grouped by API key over a date range, which distinguishes it from siblings like umbrella_api_usage_summary or umbrella_api_usage_requests. However, it lacks an explicit action verb such as 'List' or 'Get,' so it reads more like a noun phrase than a full instruction.

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 is given about when to prefer this tool over its siblings. It does not mention alternatives like umbrella_api_usage_summary, umbrella_api_usage_requests, or umbrella_api_usage_responses, nor does it state conditions such as 'use when you need per-key breakdowns.'

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