Start Interactive Session

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

The description adds that it returns a session ID for further interaction and relates to sibling session tools. With annotations indicating openWorldHint=true and not idempotent, the description confirms an interactive external process. It does not detail side effects, resource limits, or error conditions, but annotations reduce the burden.

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 concise with a clear front-loaded purpose, followed by parameter list, return value, and examples. Every sentence adds value without superfluous text.

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 tool that starts interactive sessions, the description covers essential aspects: command, args, cwd, return session ID, and examples with common use cases. It references companion tools (fc_read_output, fc_send_input). Minor gaps like error handling or timeout are not covered, but overall it's complete for the tool's complexity.

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?

Input schema coverage is 100%, so the schema already documents all parameters. The description repeats parameter names and types, adding limited value with examples (e.g., command='python'). Baseline 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 it starts an interactive process as a session, specifying the verb 'starts' and resource 'session'. It distinguishes from sibling tools like fc_list_processes and fc_kill_process by mentioning it's for interactive sessions used with fc_read_output and fc_send_input.

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 examples (Python REPL, Node REPL, PowerShell) and implies usage for interactive sessions, but does not explicitly state when not to use or provide direct alternatives. The guidance is implied rather than explicit.

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