Does 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 elsewhere. The description adds little beyond that: 'capabilities and input contract' gestures at return content, which the output schema already documents, and it says nothing about cost, latency, or when the capability listing might be stale.

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 eight-word sentence with no filler, and the subject of the return value is front-loaded. It is efficient, though its brevity edges toward under-specification rather than pure conciseness.

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 introspection tool with an output schema, the essentials are technically present, but the description omits the one thing an agent most needs: that this is the discovery/onboarding call to make before invoking the mutation and verification siblings. Against a nine-tool sibling set, that gap is meaningful.

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 no parameter semantics burden and the baseline of 4 applies. Nothing in the description conflicts with the empty input schema.

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 says it returns 'the bridge's capabilities and input contract', a coherent verb+resource statement, but it doesn't reconcile the name 'describe_agent' with 'the bridge', leaving slight ambiguity about what object is being described. It also never distinguishes the tool from siblings like resolve_agent or list_registrations, which an agent could plausibly pick instead.

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?

There is no explicit when-to-use guidance, no stated prerequisites, and no named alternative. The phrase 'input contract' faintly implies it should be called before other tools, but that inference is left entirely to the reader rather than stated.

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