create_service_env

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

No annotations, so description carries full burden. It discloses the is_build_time limitation. Lacks details on whether it overwrites existing keys, idempotency, or auth requirements. Reasonable for a simple create, but not fully transparent.

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 sentences with no waste. First sentence gives purpose, second provides critical caveat. Front-loaded and efficient.

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?

No output schema, so return value is not described. Does not mention that the service must exist or potential error scenarios. Slightly incomplete for a creation tool, but adequate given simplicity.

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 100%, so schema already documents parameters. Description adds valuable context for is_build_time: 'Has no functional effect on services'. This supplements the schema description. Other parameters are adequately described by 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?

Description clearly states the verb ('Create'), resource ('environment variable'), and context ('for a service'). It distinguishes from siblings like create_application_env by specifying 'service's environment'. The note about is_build_time adds specificity.

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?

Describes when to use: to add a key-value pair to a service's environment. Provides important caveat about is_build_time having no effect. However, does not explicitly contrast with bulk_update_service_envs or mention prerequisites.

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