list_active_services

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

Adds behavioral context: returns services sorted by cost, period filtering. But lacks details on pagination, limits, or response shape. No annotations to lean on.

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?

Well-structured with overview, usage, and parameter details. Some redundancy (e.g., 'List every...' and 'Works for any...'), but overall efficient and front-loaded.

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?

Covers purpose, usage, parameters, and examples. Lacks output format details (e.g., what fields are returned), but sufficient for a discovery tool. Output schema absent, so description could be more complete.

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 has 0% coverage, yet description explains all three parameters with format, default values, and valid values for provider. Fully compensates for missing schema descriptions.

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?

Clearly states verb 'list', resource 'active services with spend', and scope 'across AWS, Azure, and GCP'. It also mentions sorting by cost, distinguishing from siblings like list_accounts or get_cost_*.

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?

Explicitly says 'Use this to discover what services are running before querying a specific one.' Provides example queries. Could be more explicit about when not to use, but clear enough.

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