agent-friend

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

With no annotations provided, the description carries full burden and effectively discloses key behaviors: it describes the return format (string or 'null'), handling of unset variables, and security behavior for sensitive variables (hidden values). It does not cover error conditions, rate limits, or authentication needs, but provides sufficient operational context for a read-only tool.

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 front-loaded with the core purpose in the first sentence, followed by essential behavioral details. Every sentence adds value: the first defines the action, the second specifies return types, and the third covers security handling. There is no redundant or vague language, making it efficiently structured.

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 no annotations, 0% schema coverage, but an output schema exists, the description provides adequate context for a simple read operation. It explains return values and security behavior, though it could benefit from mentioning error cases or input examples. The output schema likely details the return structure, reducing the need for full output explanation in the description.

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 schema provides no parameter descriptions. The description does not explicitly mention the 'key' or 'default' parameters, though it implies 'key' by referring to 'a single environment variable'. It adds no details on parameter formats, constraints, or the purpose of 'default'. Baseline 3 is appropriate as the description partially compensates but leaves parameters under-documented.

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 clearly states the specific action ('Get the value'), target resource ('a single environment variable'), and output behavior ('Returns the value as a string, or 'null' if not set'). It distinguishes from sibling tools like env_env_list (which lists all variables) and env_env_set (which sets values) by focusing on retrieving a single variable's value.

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 implicitly indicates usage context by specifying it retrieves a single variable's value, contrasting with env_env_list for listing all. However, it lacks explicit guidance on when to use alternatives like env_env_check or env_env_load, and does not mention prerequisites or exclusions, such as permission requirements or system limitations.

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