get_default_session

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 reveals the dependency on environment variables and conditional return, but does not disclose what happens if auto-authentication fails (e.g., returns null or error) or whether it is a safe read operation.

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 a single sentence with no wasted words, efficiently conveying the tool's purpose and condition.

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 has no parameters, an output schema, and simple behavior, the description is nearly complete. It could mention the failure case for full completeness, but overall it adequately informs the agent.

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?

There are no parameters, so the schema coverage is 100% trivially. The baseline for 0 parameters is 4, and the description adds value by explaining the conditional behavior of the tool, earning an extra point.

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 verb (returns) and resource (default session ID), with a specific condition (if auto-authentication succeeded). It distinguishes itself from sibling tools like 'login' and 'session_status' by focusing on automatic authentication from environment 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 description implies when to use (after setting environment variables for auto-auth) and provides context, but does not explicitly state when not to use or mention alternatives like 'login' or 'session_status'.

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