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

With no annotations provided, the description carries the full burden of behavioral disclosure. It does not state the time window covered, whether spend is aggregated or itemized, or whether results are ordered or paginated.

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?

Two short sentences with no filler and the core scope ('per agent in the workspace') front-loaded. Efficient, though the second sentence is more marketing framing than functional detail.

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?

No output schema and no annotations, so the description should describe the return shape (agent identity plus credit total), any time period, and ordering. It says only 'total credit spend per agent,' which is too thin for a reporting tool with zero structured coverage.

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?

The tool has zero parameters, so there is nothing for the description to clarify and the baseline is 4. The description's mention of workspace scope is adequate given no inputs exist.

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 metric (total credit spend) and dimension (per agent within the workspace). However, it does not explicitly distinguish itself from close siblings like get_credit_usage_for_agent, get_credit_usage_by_type, or get_credit_usage_monthly, leaving the agent to infer the difference.

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 when-to-use guidance, no exclusions, and no mention of alternatives such as get_credit_usage_for_agent or get_credit_usage_by_type. The tagline 'Identifies the most expensive agents' hints at a use case but is not explicit routing guidance.

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