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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions cost savings and simulation but does not explain what starting a session entails, any side effects, credit consumption, or reversibility. For a session-creating tool, this lack of transparency is a significant gap.

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 concise, using two short sentences to state the primary action and its value proposition. There is no unnecessary detail or repetition of schema information.

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 one-parameter tool, the description covers the core purpose and usage context. However, it does not explain the session lifecycle or relationship to sibling tools like end_sdac_session or run_sdac_trial. The lack of an output schema also leaves return values unspecified, but this is a minor gap for such a simple operation.

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 schema already provides a full description for the sole parameter auth_token, and the tool description adds no additional parameter information. Since schema coverage is 100%, the baseline score of 3 is appropriate.

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 'Start a simulation session' with a specific verb and resource. It also distinguishes itself from real decision creation by mentioning 'before creating real decisions', making the tool's purpose distinct from siblings like create_decision.

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 clear context that this tool is for testing EE combinations at a fraction of the cost before committing to real decisions, implying its use as a low-cost simulation alternative. However, it does not explicitly name alternative tools or state exclusions, which would make it a 5.

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