get_coverage

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

Annotations already declare readOnly, idempotent, non-destructive, closed-world, so repeating 'Read-only' adds nothing. However the description discloses two non-obvious behaviors beyond the annotations: rows are newest-first, and totals aggregate the full filtered range regardless of limit. That is real behavioral 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?

Front-loaded with purpose, then alternatives, then parameter behavior, then ordering and read-only note. Every sentence earns its place, though the trailing 'Read-only' is redundant with the annotations and the multi-clause structure is slightly dense.

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?

An output schema exists, so return format need not be explained. With purpose, alternatives, filtering semantics, ordering, and aggregation behavior all covered, an agent has everything needed to call this correctly.

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, but the description adds meaning the schema does not: date_from/date_to filter by chunk month (not filing or ingestion date), and limit caps rows while totals stay unaffected by it. That clarification materially changes how limit is used.

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 verb and resource — reporting scrape coverage per monthly chunk, with totals — and explicitly contrasts itself with get_statistics and verify_sinks in the sibling list. An agent can distinguish it from every listed sibling without opening a schema.

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?

Names two alternatives with the exact condition that selects each: get_statistics for filing counts grouped by a dimension, verify_sinks for cross-sink comparison. Explicit routing guidance, not merely implied context.

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