UK Legal Research MCP Server

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

Annotations already provide readOnlyHint=true, destructiveHint=false, idempotentHint=true, and openWorldHint=true, covering safety and idempotency. The description adds valuable behavioral context beyond annotations: it specifies that it 'fetches the judgment XML from TNA and parses all OSCOLA citations within it', and describes output behavior ('returns citations grouped by type', 'each bucket is de-duplicated and sorted'), which helps the agent understand processing steps and result formatting.

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 efficiently structured in three sentences: the first states the purpose and scope, the second explains the process, and the third details the output behavior. Each sentence adds essential information without redundancy, and it is front-loaded with the core functionality, making it easy to parse quickly.

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 (parsing citations from XML), rich annotations (covering safety and idempotency), and the presence of an output schema (implied by 'Has output schema: true'), the description is complete. It explains what the tool does, how it processes data, and the format of results, providing sufficient context for an agent to use it effectively without needing to detail return values explicitly.

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%, with the parameter 'case_uri' well-documented in the schema (including format examples and restrictions). The description does not add any parameter-specific information beyond what the schema provides, such as clarifying the 'case_uri' usage or additional constraints. With high schema coverage, the baseline score of 3 is appropriate as the description does not compensate but also does not detract.

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 specific action ('Map all citations within a judgment'), the resource ('judgment XML from TNA'), and the scope ('cases cited, legislation referenced, SIs, EU law'). It distinguishes itself from sibling tools like 'citations_parse' and 'citations_resolve' by focusing on comprehensive network mapping rather than parsing or resolving individual citations.

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 implies usage context by specifying it works with 'judgment XML from TNA' and requires a 'TNA judgment URI slug', providing clear prerequisites. However, it does not explicitly state when to use this tool versus alternatives like 'case_law_search' or 'citations_parse', nor does it mention exclusions or edge cases.

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