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

Annotations already declare readOnlyHint=true, destructiveHint=false, openWorldHint=false, so the safety profile is covered. The description adds a genuinely useful operational constraint beyond that: it requires an API key with read scope, and it discloses the shape of the returned payload.

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 compact sentence covering resource, identifier, return fields, and auth requirement with no filler. The auth requirement sits at the end rather than being front-loaded, which is a minor structural quibble.

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 simple single-parameter read tool with no output schema, the description supplies exactly what is needed: how to identify the record and what comes back, including the raw design params field that would otherwise be invisible. Nothing material is missing.

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?

Only one parameter and schema description coverage is 100%, so the schema already documents that designId comes from list_designs or save_design. The description's 'by id' adds no format, validation, or sourcing detail beyond the schema, matching the baseline of 3.

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 retrieval action on a named resource ('One saved design by id') and enumerates the returned fields (name, format, link, raw design params). It implicitly separates itself from list_designs by fetching one record, though it never names the sibling explicitly.

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?

Usage is implied rather than stated: the agent infers it should supply an id sourced from list_designs or save_design (that routing hint lives in the schema, not the description). No explicit when-to-use-vs-alternatives guidance is offered.

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