Upsert env var

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

With no annotations, the description carries the full burden. It discloses the 'by key' idempotent behavior, but does not mention side effects, permission requirements, or how optional flags (is_literal, is_multiline, etc.) affect behavior. This is minimal for a mutation 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 a single 12-word sentence that is front-loaded and free of filler. It is concise, though under-specified for the tool's complexity; however, conciseness itself is strong.

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 7 parameters, 0% schema coverage, no annotations, and no output schema, the description is far too minimal. It does not explain return values, side effects, or how optional parameters interact, making it incomplete for a tool of this complexity.

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 coverage is 0% and the description only references 'key' as the lookup mechanism. The other six parameters (uuid, value, is_literal, is_preview, is_multiline, is_shown_once) are completely undocumented, so the description fails to add any value beyond the schema.

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 tool creates or updates an environment variable for an application, with 'by key' signaling upsert semantics. It is specific about the verb and resource, but does not explicitly differentiate from sibling tools like createEnv and updateEnv.

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 implies when to use it (when you want to create or update an env var by key) but provides no explicit guidance vs alternatives, no exclusions, and no prerequisites. 'Create or update' gives some context, but the sibling tools createEnv/updateEnv are not mentioned.

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