Codemagic

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

With no annotations provided, the description carries full burden for behavioral disclosure but fails to disclose read-only status, pagination behavior, or return format. While 'List' implies read-only, explicit confirmation and output structure details are missing given the lack of output schema.

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 appropriately brief with the main purpose front-loaded in the first sentence. The Args section is justified given the schema's lack of descriptions, though it uses a slightly informal docstring format rather than integrating into the narrative description.

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 single-parameter read operation, the description covers the essential inputs but leaves significant gaps regarding output structure (array vs object, what fields are returned) since no output schema exists. It meets minimum viability but is not richly complete.

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?

The schema has 0% description coverage (only a title 'App Id'). The Args section in the description compensates by documenting 'app_id: The Codemagic application ID', providing necessary semantic context for the single required parameter.

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 verb (List) and resource (environment variables) with scope (Codemagic application). It implicitly distinguishes from sibling mutation tools (add_variable, update_variable, delete_variable) by using 'List' versus their action verbs, though it doesn't explicitly name alternatives.

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 provides no guidance on when to use this tool versus alternatives like add_variable or update_variable, nor does it mention prerequisites (e.g., needing the app_id from list_apps) or typical workflows.

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