render_list_env_vars

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

Without annotations, the description must convey behavioral traits. It states that the tool lists environment variables, implying a read operation, but does not mention whether values are shown, if any authentication is required (api_key hint), or if there are any limitations or side effects. This leaves key gaps for an agent.

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 a single concise sentence, which is efficient. However, its brevity comes at the cost of completeness; a slightly longer but still concise description could include parameter or usage hints. It scores well for structure but not perfectly.

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?

Given the tool has two parameters with zero schema descriptions, no annotations, and siblings with overlapping contexts, the description fails to be complete. It does not clarify what the list returns, how parameters are used, or any constraints, leaving the agent underinformed.

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 should explain parameter meaning. It does not mention api_key or service_id at all. The agent receives no context beyond the schema field names, which is insufficient for correct invocation.

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 'List environment variables for a Render service.' clearly states the verb (List) and the resource (environment variables for a Render service). This distinguishes it from sibling tools like render_list_services or render_set_env_var, which have different purposes.

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?

No usage guidelines are provided. The description does not indicate when to use this tool versus alternatives such as render_get_service (which might include environment variables) or render_set_env_var (for modifying). It also lacks prerequisites like needing a valid service_id.

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