canlii-mcp

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

With no annotations, the description carries full burden and excels: it discloses that returns are ranked by relevance, include citations and titles but not keywords/dates/URLs, date filters are unsupported, and it requires specific legal terms. It also notes the need to verify sources via URLs, adding rich behavioral context.

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 front-loaded with core purpose, followed by usage tips and constraints. Every sentence adds value—no fluff—making it efficiently structured and appropriately sized for the tool's complexity.

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?

Given the tool's complexity and lack of annotations/output schema, the description is highly complete: it covers purpose, usage, behavioral traits, limitations (no date filters), and next steps (use get_case_metadata). It provides all necessary context for effective agent use without redundancy.

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 parameters well. The description adds minimal param-specific info beyond the schema, such as implying 'query' should use specific legal terms and jurisdiction, but doesn't detail syntax or format. Baseline 3 is appropriate as the schema does heavy lifting.

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 clearly states the tool searches CanLII for cases, legislation, and commentary by keyword, specifying it's the primary entry point for legal research. It distinguishes from siblings by mentioning get_case_metadata for full details, making the purpose specific and differentiated.

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?

Explicit guidance is provided: use this for keyword-based search (not semantic), include jurisdiction to narrow results, call get_case_metadata for full details before citing, and avoid date filters. It clearly states when to use this tool versus alternatives like get_case_metadata.

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