list_session_variables

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

No annotations are provided, so the description carries the full burden. It adds meaningful behavioral traits: variables persist until the proxy is restarted and are created by extract_session_variable. While it doesn't explicitly state that the tool is read-only, that is inherent in a list operation, so this is acceptable.

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 three short sentences, with the primary action front-loaded in the first sentence. It includes only essential information—what is listed, why it matters, and its lifecycle—with no wasted words.

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 zero-parameter list tool, the description covers all essential aspects: what is listed, their purpose, how they are created, and their persistence. The output schema exists and presumably documents the return values, so no further detail is needed.

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 tool has 0 parameters and the input schema is empty. The baseline for 0 params is 4, and the description does not need to explain parameters. It makes no redundant parameter claims.

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 uses the specific verb 'list' with the resource 'saved session variables', and explains their role as {{name}} placeholders in replay_flow. This clearly distinguishes it from sibling tools like extract_session_variable, which creates them, and replay_flow, which consumes them.

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 useful context by stating that variables are created by extract_session_variable and used in replay_flow, implying when listing them is relevant. It does not explicitly say 'use this when' or name alternatives, but there is no competing list tool among siblings, so the context is clear enough.

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