function.variables

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

With no annotations provided, the description must disclose all behavioral traits. It merely states 'List function variables' without clarifying whether the operation is read-only, if it requires specific permissions, or what side effects may occur. The behavior is implied but not 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?

The description is extremely short (4 words), which initially suggests conciseness, but it sacrifices essential information. With two required parameters and a large sibling set, the description is under-specified and not appropriately sized for the tool's complexity. It lacks front-loading of key details.

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 tool requires two required parameters, has no output schema, no annotations, and exists among dozens of similar function-related tools, the description is severely incomplete. It fails to explain the tool's purpose, parameters, return values, or usage context, leaving the agent critically underinformed.

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 0%, meaning the input schema provides no textual explanation for either parameter (session_id, function_start). The tool description adds nothing to explain what these parameters mean or how to use them, failing to compensate for the lack of schema-level descriptions.

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 'List function variables' specifies a clear verb (List) and resource (function variables), but does not differentiate from closely related siblings like function.var_refs or function.var_refs_from. The purpose is vaguely stated without scope or context, making it adequate but ambiguous among similar tools.

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?

No usage guidelines are provided. The description does not state when to use this tool over alternatives, nor does it mention prerequisites, exclusions, or context. The agent has no guidance on selecting this tool from the extensive sibling list.

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