get_session_vars

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

With no annotations, the description carries the behavioral disclosure burden. 'List' strongly implies a non-mutating, read-only operation, and 'persistent Python session' adds useful state context. However, it does not disclose behavior for invalid or expired session IDs, or clarify that only names are returned rather than values, though the output schema likely covers return shape.

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 one efficient sentence with no filler and the key action is front-loaded. It is appropriately concise for a simple tool, though it could have used one additional clause to explain session_id provenance.

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 low-complexity tool with an output schema, the description provides the core purpose but leaves some context gaps. It does not mention session lifecycle dependencies, how to obtain session_id, or when this tool is preferable to related session tools. Still, the parameter name and sibling context make the intended use reasonably inferable.

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%, so the description must compensate for the undocumented session_id parameter. It does not explain where session_id comes from or that it should be the ID returned by begin_session. The parameter name is somewhat self-explanatory, but the description adds no real semantic detail beyond the schema itself.

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 a specific verb ('List') and a clear resource ('variable names in a persistent Python session'). This clearly distinguishes it from sibling tools like begin_session, exec_in_session, and end_session, since none of those are about listing existing Python variables.

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 phrase 'persistent Python session' implies the tool is meant to be used while a session is active, but the description does not explicitly state when to use it versus alternatives like exec_in_session or get_cvar. There is no precondition mentioned, such as needing a session ID from begin_session.

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