list_rules

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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint: false, so the safe, read-only nature is covered. The description adds useful behavior beyond the annotations by revealing that the catalog is static and cacheable, plus it enumerates the return content. There is no contradiction, and the added context is meaningful but not extensive.

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?

Three sentences, each earning its place: the first identifies the scope, the second states the return shape, and the third gives caching and cross-tool usage guidance. The most important action word and object are front-loaded, with no filler or repetition of annotation data.

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 zero parameters, an output schema, and annotations covering the read-only/idempotent behavior, the description covers everything an agent needs: what is returned, what standards are included, and how to use the output with explain_rule. Nothing material is missing.

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 tool has zero parameters, so there is no parameter meaning to clarify beyond the empty input schema. The description instead clarifies the output shape (rule IDs, severities, descriptions, external standards), which is the relevant semantic information for a no-argument list tool.

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 clear verb and resource: 'List the full catalog of validation rules available in vastlint.' It also scopes the result by standard and version (VAST 2.0-4.4, VMAP 1.0, DAAST 1.0/1.1) and names the output fields, making it unambiguous what the tool returns. It additionally distinguishes itself from sibling explain_rule by positioning list_rules as the source of rule IDs for that tool.

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 gives explicit operational guidance: 'Call this once and cache the result — the catalog is static.' It also tells the agent how to use the result with a sibling tool: 'Use rule IDs from this list with explain_rule for full details and fix guidance.' This makes the selection and follow-up action obvious.

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