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 covered. The description adds non-obvious behavioral context by naming what is returned (source URL and file hash) and by contrasting the hosted surface with the full local package.

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 tight sentences with the core action front-loaded and no filler. The scope-contrast clause is dense but does real work, so nothing is wasted.

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 small read-only two-parameter tool with no output schema, the description covers the action, the return payload (source URL, file hash), and the data scope. Only the enum-constrained nature of the required 'name' parameter is left implicit.

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?

Schema description coverage is 0%, so the description must carry the weight. It partially does: 'input or output schema' maps to the 'kind' enum and 'a tool's' maps to 'name'. But it never explains that 'name' is constrained to a fixed enum list of tool identifiers, nor what the default kind value implies.

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 ('Read') and resource ('a tool's shipped input or output schema') plus the returned metadata. It clarifies its own scope (shipped package schemas) but does not explicitly distinguish itself from similarly-named siblings like 'object', 'schema', or 'registry_snapshot'.

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 implies when this tool's data applies ('Local schemas describe the full package; tools/list describes this narrower hosted surface'), which is useful scope framing. However, it never gives an explicit trigger for choosing this tool or names a sibling to prefer instead, so usage remains inferred.

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