Cost report: by-agent

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, which cover safety and idempotency. The description adds the authorization class ('board_or_agent'), which is useful but does not disclose other behavioral aspects like result format, pagination, or potential limitations. Given rich annotations, the description adds marginal value.

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 very brief (two sentences), which is concise, but it lacks structure: the title is repeated, and the technical details are crammed without clear separation. The information could be organized better for agent parsing, though it is not overly verbose.

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?

The description does not explain what the 'by-agent' report contains (e.g., cost breakdown per agent, time ranges, aggregation). An output schema exists but is not referenced. Given the complexity of cost reports and many similar sibling tools, the description is insufficient for an agent to understand the tool's output or compare with alternatives.

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 input schema has one required parameter (companyId in path) with 0% description coverage. The tool description does not explain what companyId represents, expected format, or constraints. With no parameter documentation in either schema or description, the agent cannot determine correct usage.

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 states 'Cost report: by-agent', which clearly indicates it provides cost data grouped by agent. The HTTP method and endpoint path further clarify the operation. It is distinguishable from sibling cost tools (e.g., by-agent-model, by-provider) through the name, though the description could be more explicit about the grouping.

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 on when to use this tool versus alternatives like costs_by_agent_model or costs_by_provider. The agent is left to infer from the name alone. The description does not provide context for selection, missing an opportunity to differentiate use cases.

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