get_rules

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

With no annotations provided, the description carries the burden of disclosing behavior. It states 'Does not require a browser — instant response', which adds performance and execution context. The word 'List' implies a read-only, non-destructive operation, and 'optionally filtered' clarifies behavior when no filters are supplied. It does not describe return format, but for a simple list tool this is adequate.

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 concise sentence that front-loads the core action ('List axe-core accessibility rules'), then adds filter options and a useful behavioral note. No wasted words; every clause earns its place.

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 3 optional parameters, no output schema, and no annotations, the description covers the main aspects: what it lists, how to filter, and that it is instant and browserless. It does not mention return structure, but that is not essential for a list operation, and the sibling get_rule_info presumably handles detailed rule information.

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 each parameter (level, search, criterion) having its own description. The tool description adds a summary of filtering ('by WCAG level, criterion, or search term') but no additional detail beyond what the schema provides. This is consistent with 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 uses the specific verb 'List' with the resource 'axe-core accessibility rules' and mentions optional filtering by WCAG level, criterion, or search term. This clearly distinguishes it from siblings like audit_url/audit_html (which perform audits) and get_rule_info (which focuses on a single rule).

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 when to use this tool: to list rules without requiring a browser, providing instant responses. It does not explicitly mention alternatives or when not to use it, but the contrast with browser-requiring audit tools is implicit. The lack of explicit exclusions keeps it from a 5.

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