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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the safety profile is covered. The description adds value by disclosing that the response includes bundled resource links and download metadata, giving the agent concrete expectations about the tool's behavior beyond 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 one efficient sentence that front-loads the action, target, and key identifier. Every phrase earns its place, and there is no redundant wording or filler.

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?

This is a simple single-parameter lookup tool with a full input schema, an output schema, and read-only annotations. The description states what is fetched and what is included; nothing needed for correct invocation 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?

Schema description coverage is 100% and the slug parameter is documented as 'Starter kit slug.' The description repeats that the lookup is 'by slug' but adds no new format, precedence, or value constraints beyond the schema. Baseline 3 is appropriate when the schema already fully documents the parameters.

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 the specific verb 'Fetch' with a concrete resource: 'one starter kit by slug'. It also names what is included ('bundled resource links and download metadata'), which distinguishes it from list-style siblings like list_kits and other resource fetchers.

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 clearly frames when to use this tool: when you need a single starter kit identified by slug. It does not explicitly name alternatives or exclusions, but the singular 'one' and the slug parameter imply a lookup use case that is distinct from listing or running diagnostics.

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