Check legal citations in text

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

Beyond the annotations (readOnly, openWorld, idempotent, non-destructive), the description details the output structure (coverage statement, counts per tier, red/orange rows), the meaning of red and orange (check this vs cannot verify), and the deep mode behavior (slower, opt-in, limited to 3/month, answers are a review queue not a verdict). It also discloses free tier limits and API key lifting. No contradictions with annotations.

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 long but every sentence carries critical information. It is front-loaded with the core function, then usage, then output details, limitations, deep mode, and free tier. It is organized logically without redundancy, making efficient use of the reader's attention.

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?

This is a complex tool with no output schema, so the description must explain the return values. It does: coverage statement, counts per tier, one line per row needing human, number of citations, and report id for render_report. It also explains what it cannot do and the meaning of red/orange. The description fully equips an agent to call the tool correctly and interpret results.

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?

Although schema coverage is 100%, the description adds substantial meaning to the 'deep' parameter: it explains that it checks whether the opinion supports the sentence, is slower (1-2s per citation), sends the clause to a model judge, is limited to 3/month, and returns a review queue. For 'text', the schema already describes it, but the description reinforces its use for prose. The description adds value beyond the schema.

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 verb and resource: 'Check every case citation in a text against proofread.law's register of about 10 million US court opinions'. It also specifies the use case (draft brief, memo, letter) and differentiates from siblings by explicitly stating what it cannot do (resolve WL/Lexis, check statutes/regulations).

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?

It explicitly instructs when to use it: 'Use it on a draft brief, memo, letter or any prose that cites cases, before the citations are relied on.' It also lists exclusions (cannot resolve WL/Lexis, check statutes, etc.) and describes the deep mode option with clear trade-offs (slower, opt-in, limited). This provides clear guidance for selecting this tool over alternatives.

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