List variables

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

The readOnlyHint: true annotation already covers the read-only nature, but the description provides no additional behavioral context such as what variables are included, whether it respects filters, or how results are paginated. The description merely restates the action without extra transparency.

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 extremely concise and front-loaded, with no filler words. It is appropriately short for a simple listing action, though it could add minimal detail without becoming verbose.

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?

With 5 parameters, an output schema, and related sibling tools, the description is insufficiently complete. It does not mention filtering scope, defaults, or use cases, leaving significant gaps. The output schema exists but the description does not help the agent understand how to invoke the tool effectively.

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 description adds no meaning for any of the 5 parameters. Schema description coverage is 0%, and the description does not mention kind, name_filter, max_variables, or promoted_only, leaving all parameters undocumented.

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 action ('List') and the resource ('variables in the cycle model'), which is specific and distinguishes it from siblings like get_outputs or set_inputs. However, it does not explicitly differentiate its scope (e.g., inputs vs outputs vs both), so it falls short of a 5.

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 gives no indication of when to use this tool versus alternatives such as get_outputs or get_cycle_summary. It lacks any usage context, prerequisites, or exclusions, leaving the agent to guess.

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