create_session

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

With no annotations, the description must carry the behavioral disclosure burden. It communicates key behavior: the session is persistent and the tool returns an identifier for later use. However, it does not mention lifecycle, cleanup, side effects, or what 'persistent' means in terms of resource usage, leaving important behavioral traits undisclosed.

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?

Two short sentences, front-loaded with the core action, no filler or repetition. The description is compact and easy to parse.

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?

The definition is too sparse for a tool with no output schema and zero parameter documentation. The agent is not told what persist_changes does, how the returned session ID is consumed, or what prerequisites exist for the file, so it cannot confidently invoke the tool correctly in context.

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 parameters, but it does not. It never mentions file_id or persist_changes, leaving the agent to guess their meaning, requiredness, or effect.

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 names a specific verb ('Create'), a concrete resource ('persistent Excel session'), and its purpose ('for batch operations'), and notes it returns a session ID. This clearly distinguishes it from siblings like create_upload_session and the many read/write 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?

The phrase 'for batch operations' gives a clear indication of when the tool is appropriate, implying it should be used as a precursor to grouped Excel operations. It does not explicitly name alternatives or exclusions, but the context is reasonably clear.

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