get_org_cost_summary

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

Even with no annotations, the description outlines the output structure (total, per-account, top services) and the parameter behavior (look-back period). It does not disclose potential behaviors like pagination or rate limits, but the tool is simple and read-only, so the transparency is adequate.

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 front-loaded with the core purpose, followed by a clear args section and relevant examples. Every sentence adds value with no redundant information.

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 fully covers what the tool returns (total spend, per-account breakdown, top services) and specifies the required plan, which is sufficient given the simple parameter and lack of output schema.

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 description includes the parameter name and purpose ('Look-back period in days (default 30)'), adding value beyond the schema which only provides type and default. However, with only one parameter and schema coverage 0%, the description does not provide extensive additional context.

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 it retrieves a cost rollup across all AWS Organization accounts, including total spend, per-account breakdown sorted by spend, and top services per account. This distinctively separates it from siblings like get_cost_summary (likely single account) and get_cost_summary_all_accounts.

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?

The description mentions the prerequisite 'Requires a Team plan (org_reports)' and provides example queries that illustrate typical use cases. However, it does not explicitly contrast with alternatives or mention when not to use.

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