describe_capabilities

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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds behavioral context beyond that: it explains the distinction between existing capabilities and enabled ones (available_but_disabled field), and states that the policy is immutable from this environment. This is valuable context not present in the annotations.

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 concise and well-structured. It front-loads the core purpose, then immediately provides a usage directive, highlights the key field, and closes with a policy note. Every sentence carries meaningful information without redundancy or fluff.

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 zero-parameter tool with an output schema and annotations covering safety, the description is complete. It tells the agent what the tool does, when to call it (after refusal), how to interpret the critical output field, and what limitations exist (immutability). An agent would have no gaps in knowing when and how to use this tool correctly.

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 the schema provides full coverage and the description correctly does not attempt to document parameters. The description focuses on the tool's behavior and output interpretation, which is appropriate. Baseline for 0 params is 4, and nothing here warrants a downgrade.

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 purpose: describing what the install is permitted to do and what it could do if reconfigured. It uses a specific verb ('describe') and resource ('capabilities'), and distinguishes itself from siblings by focusing on permission introspection rather than access checks, problem reporting, or course listing.

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 usage guidance: 'Call this after a refusal.' It also explains how to interpret the results, specifically telling the agent to inform the user of the setting to change when a capability is listed as available_but_disabled. It does not mention alternatives, but the context is clear and no alternative is needed.

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