List Billing Periods

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

Annotations already provide readOnlyHint=true, etc. The description adds pagination details and mentions required project_id. However, the erroneous mention of 'Commitments' could confuse the agent about the return type, which is a transparency issue.

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 reasonably structured with front-loaded purpose, but it includes redundant API details and the erroneous 'Commitments' statement. It could be shorter and more accurate.

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 exists, so the description should explain the return value. It incorrectly says 'paginated JSON array of Commitments' instead of billing periods. It also omits details about what fields are in each billing period object, leaving the agent underinformed.

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 100%, so baseline is 3. The description adds little beyond schema: it notes project_id is required and mentions page/per_page for pagination but does not explain filter parameters. This meets the baseline but adds minimal value.

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 it returns a list of Billing Periods for a project, which is correct. However, it then says 'Use this to enumerate Commitments' and 'Returns a paginated JSON array of Commitments,' which is contradictory and misleading. This error reduces clarity.

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?

It provides usage context: 'when you need a paginated overview, to find IDs, or to filter by query parameters.' It does not explicitly state when not to use or compare to alternatives like show_billing_period_for_project, so it's adequate but not strong.

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