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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, covering the safety profile. The description adds useful context that values are not secrets and need no masking, but omits return format, pagination, or project-resolution behavior.

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, front-loaded with the core action and clarifying the non-secret nature, then routing to the sibling. No wasted words.

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 2-param read tool with strong annotation coverage, the description covers the key distinction (non-secret vs secret) and points to the alternative. Missing parameter guidance for limit/project_id keeps it from a 5.

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% and both parameters (limit, project_id) are undocumented in the schema. The description mentions 'a project's ... variables' implying project_id, but adds no detail on the limit parameter or format. Baseline 3 given minimal compensation.

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 (List) and resource (a project's non-secret Function variables, including values). It distinguishes itself from list_secrets, though it doesn't explicitly differentiate from other list_* siblings like list_functions or list_deployments.

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?

Explicitly routes the agent to list_secrets for credentials, providing a clear when-to-use-this-vs-alternative signal. However, it doesn't state when-not to use it or list other relevant alternatives.

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