WCAG MCP Server

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It states the tool 'gets' data, implying a read-only operation, but doesn't specify whether it requires authentication, has rate limits, returns paginated results, or what the output format looks like. This leaves significant gaps for a tool that likely queries a database or API.

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 a single, efficient sentence that directly states the tool's purpose with zero wasted words. It is appropriately sized for a simple lookup tool and front-loads the key information without unnecessary elaboration.

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 lack of annotations and output schema, the description is incomplete. It doesn't explain what the tool returns (e.g., a list of failure descriptions, error codes, or structured data), how failures are defined, or any behavioral traits like error handling. For a tool with one parameter but no structured output documentation, more context is needed.

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?

The input schema has 100% description coverage, clearly documenting the single required parameter 'ref_id'. The description adds no additional parameter semantics beyond what the schema provides, such as examples of valid reference numbers beyond '1.1.1' and '2.4.7', or how failures are structured. This meets the baseline for high schema coverage.

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 verb 'gets' and the resource 'failure techniques (common mistakes)' for a specific success criterion. It distinguishes the tool's focus on failures from other tools that might retrieve criteria or techniques more broadly, though it doesn't explicitly differentiate from siblings like 'get-techniques-for-criterion' which might return all techniques rather than just failures.

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 provides no guidance on when to use this tool versus alternatives. It doesn't mention when-not scenarios, prerequisites, or compare it to sibling tools like 'get-techniques-for-criterion' or 'get-criterion', leaving the agent to infer usage from the name and description alone.

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