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

Beyond the readOnly/openWorld annotations, it discloses meaningful traits: values the publisher later overwrote stay visible (data retention behavior), the free tier covers only the last 30 days, and responses carry observed_at, source URL, raw-file sha256, tracking_since and fetch gaps. This is substantive behavioral context the annotations do not provide.

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 the core question and the change types, then supporting provenance details and constraints. Dense but each clause carries information; no filler sentences.

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?

For a versioned change-history tool with a full schema and an output schema, the description covers the important semantics (what a revision means, overwrite visibility, free-tier window). It is essentially complete for correct invocation, missing only explicit sibling routing.

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 description coverage is 100%, so the schema already documents all five parameters including formats and the enum. The description adds only light mapping (dataset types, 'revised with the old value'), so the baseline 3 is appropriate.

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 a specific resource and scope: recorded changes (new weeks and revisions) in influenza figures for a Japanese region since a date. The change-log framing implicitly distinguishes it from the snapshot sibling, though it never names flu_region_snapshot directly.

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?

Usage is implied by 'since a date' and the change-tracking framing, which suggests this tool answers 'what changed' questions rather than 'what is the current state'. However, it never states when to prefer this over flu_region_snapshot or catalog, nor any exclusions.

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