list_diagnosticsLists registered diagnostic rules and supported problem types, so you can identify which checks apply before diagnosing hook, plugin, skill, or configuration issues.
List registered diagnostic rules and supported problem types.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint, idempotentHint, destructiveHint=false and openWorldHint=false, so the safety profile is fully covered without the description's help. The description adds only a small amount of scope information (that the listing covers both rules and problem types), which is modest value beyond structured data.
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?
A single front-loaded sentence that states verb, resource and scope with no filler or redundancy.
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?
With zero parameters, full annotation coverage, and an output schema that documents the return shape, the description carries no remaining burden for correct invocation. Only the missing relationship to the 'diagnose' sibling keeps it from a 5.
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 takes zero parameters, so there is nothing for the description to disambiguate; baseline 4 applies. The description correctly implies no filtering options exist.
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?
States a specific verb (List) and resource (registered diagnostic rules, supported problem types), so the agent knows exactly what comes back. It does not differentiate itself from the sibling 'diagnose', which presumably runs a diagnosis rather than enumerating rules, so it falls short of a 5.
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 listing nature implies discovery usage (call it to learn which rules exist before invoking 'diagnose'), but the description never says when to use it, when not to, or that 'diagnose' is the execution counterpart. Usage is left to inference.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.