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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds real value beyond that: it states that only environment variable references are returned and that no keys, prompts, network calls, or file writes occur, which tells the agent exactly what the output does and does not contain.

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?

Three short sentences, front-loaded with purpose and immediately followed by the output guarantee. The only filler is the trailing compatibility caution, which is vague but cheap.

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?

With no output schema, the description correctly compensates by describing the return content (env var references only, no secrets). It is nearly complete for this tool, missing only an explanation of the format/locale choices.

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 has to carry the parameter burden. It meaningfully constrains 'selections' (1–5 exact catalog pairs), but says nothing about the 'format' or 'locale' enums, which are the two parameters an agent most needs to reason about.

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 ('Render') and a specific resource ('keyless config') with an explicit scope (1–5 exact catalog providerSlug/modelSlug pairs). No sibling tool produces config output, so the purpose is unambiguous.

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 only guidance is the vague caution 'Review compatibility before using,' which does not say when to choose this tool, how to pick between the route-pack/litellm/env-template formats, or what 'compatibility' means. No alternatives are named.

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