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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the description is not required to restate safety. It adds valuable behavior: it 'surfaces the real rules and numbers' rather than opinions, explicitly does not rank, and discloses the subscription requirement ('Requires an active Bidda subscription') and how to pass the key (api_key). This goes beyond the schema by framing the tool's output philosophy and access prerequisite, though it does not detail error handling or return format.

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 60 words across three sentences, each earning its place: the first defines the core purpose and an illustrative example, the second clarifies the non-ranking behavior and focus on real data, and the third covers authentication requirements. It is front-loaded with the most important information and contains no redundant filler.

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 tool with only two params and no output schema, the description gives adequate context for correct invocation: what topic to provide, what the tool does, what it does not do, and the required authentication. The main gap is the lack of any description of the response format; while 'surfaces the real rules and numbers' hints at the content, an agent might benefit from knowing whether results are returned as a table, list, or structured document. With no output schema, a short note on return structure would complete the picture. Still, this is a minor omission given the strong clarifying statements elsewhere.

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% and both parameters are described: topic includes an example, and api_key has a thorough explanation of header vs argument precedence and free trial inclusion. The description does not add significant new parameter-level meaning beyond what the schema already provides; it only corroborates the api_key need. Baseline 3 is appropriate because the schema fully documents parameters.

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 opens with a clear verb and resource: 'Compare how different jurisdictions address a compliance topic, side by side.' It specifies the scope (jurisdictions, compliance topics) and the distinctive behavior of surfacing numeric thresholds (e.g., 72 hours vs 30 days). This distinguishes it from sibling tools like get_jurisdiction_bundle or check_action_compliance, and it states explicitly that it does not rank jurisdictions, removing ambiguity about its output philosophy.

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 clearly defines when to use the tool: when a side-by-side comparison of jurisdictions' rules on a compliance topic is needed. It also implies a contrast with ranking tools by stating 'does not rank which jurisdiction is stricter.' However, it does not explicitly name alternative tools for different use cases (e.g., single-jurisdiction lookup or compliance checking), nor does it state conditions when not to use this tool. It gives clear context but lacks explicit exclusionary guidance.

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