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

Annotations already establish read-only, idempotent, open-world, and non-destructive behavior, so the bar for additional disclosure is lower. The description adds useful behavioral context: it returns a 'compact roster' filtered to capabilities with enabled providers, includes only the best conformance per capability, and is intended as a one-time self-introspection snapshot. This goes beyond the structured annotations without contradicting them.

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 two sentences with no redundancy. The first sentence front-loads the core behavior and output shape, while the second sentence adds a practical usage instruction. Every part 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?

Given the tool's low complexity, zero parameters, and rich annotations, the description covers the essential aspects: what is returned, how it is organized, and when to call it. It does not detail the exact output schema, but the phrase 'compact roster... grouped by category' is sufficient for an introspection tool with no pagination or input.

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, and the baseline for no-parameter tools is 4. The description does not fabricate parameter details and accurately reflects that no input is required, so no further semantic content is needed.

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 names a specific verb and resource ('Return a compact roster of every capability with at least one enabled provider') and adds precise qualifiers: grouping by category and best current conformance. It clearly distinguishes itself from sibling introspection tools by focusing on currently available capabilities with enabled providers, not discovery or specification.

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 second sentence gives explicit when-to-use guidance: call once at the start of a task before deciding whether to attempt a capability or tell the user it isn't possible. It clearly explains the decision context, though it does not name alternative sibling tools or explicitly state when not to use this tool.

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