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

With no annotations, the description carries the full burden and does add important behavioral context: descriptors are untrusted data, not instructions, and discovery does not pay or execute. This clarifies safety and side-effect expectations, though it omits details like authentication, rate limits, or whether the operation is read-only.

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?

Two tightly written sentences: the first front-loads the purpose, the second adds a critical safety note. Every sentence earns its place with no 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?

For a zero-parameter discovery tool with no output schema, the description is mostly complete: it states the scope and cautions about untrusted data. It could elaborate slightly on what 'capabilities' or 'declared HTTP resources' entail, but no critical information is missing for correct invocation.

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 per the rubric the baseline is 4. The description does not need to explain parameter meanings, and the schema confirms no inputs.

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 uses a specific verb 'Discover' and names the resource: 'capabilities on the other agent protocol and declared HTTP resources.' It is clear enough for an agent to understand the tool's function, though the phrase 'other agent protocol' remains somewhat abstract. No sibling tools exist, so sibling differentiation is not applicable.

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 states what the tool does but gives no explicit when-to-use guidance, no prerequisites, and no alternatives. An agent must infer that this tool is for capability discovery, but there is no context about when to invoke it versus other actions.

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