List Variables

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

With readOnlyHint=true already declared, the description adds valuable behavioral context by explaining how document and page consumer scans handle failures differently. This goes beyond the annotation by disclosing error-reporting behavior, which is useful for selecting the right mode.

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 two sentences, front-loaded with the main purpose and followed by a concise explanation of consumer scan behavior. Every sentence earns its place with no redundancy or filler.

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?

The tool is a read-only listing operation with an output schema and good annotations. The description covers the primary use cases (list all, detailed info, consumer scans) and error-handling nuances. Minor ambiguity around 'local' scope and the `coverage` field exists, but overall it is complete enough for an agent to use correctly.

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 100%, so the baseline is 3. The description reinforces parameter behavior (e.g., variableId optional, includeConsumers modes) but does not significantly add beyond the schema. The failure-reporting detail is behavioral output context rather than parameter semantics.

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's function: 'List local variables/collections, or detailed info for specific variable ids; optionally scan for consumers.' This uses a specific verb (list) and resource (variables/collections), and distinguishes it from sibling mutation tools like variable_manage and variable_delete.

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 context for using the consumer scan modes: document scans isolate page failures and report them in `coverage`, while page-scoped failures return structured errors directly. It implies this is for read-only inspection versus alternatives like variable_manage, though it does not explicitly state exclusions.

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