Start a Perssua session

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

Annotations already indicate readOnly=false and destructive=false, and the description adds meaningful runtime facts: the tool launches a local desktop app, only accepts local text-file paths, and silently skips binary files. It does not cover every side effect like process lifecycle or return behavior, but it goes well beyond the bare annotation profile without contradicting it.

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?

Three sentences, each earning its place: the core function, the local-vs-remote boundary, and the file/new-assistant caveats. It is front-loaded with the main purpose and contains no repetition of the title or schema fields.

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 with six optional parameters and no output schema, the description gives enough context to select and invoke it: local execution, remote alternative, file restrictions, and new-assistant alternative. The remaining gap is that it does not describe what the tool returns or what state changes occur after launch, which would be more important without the strong sibling guidance.

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 coverage is 100%, so the baseline is 3. The description adds value by grouping the parameters into a coherent invocation scenario ('optional assistant, initial prompt, free-text context, and text files') and by contributing the binary-file-skip constraint that is not present in the schema. This lifts it above the baseline.

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 states a specific verb and resource ('Launch the Perssua desktop app and start a session') and enumerates the optional payloads it accepts. It explicitly distinguishes the tool from create_session_link and create_assistant, so an agent can disambiguate at a glance.

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?

It gives explicit when-to-use and when-not-to-use guidance: local same-machine usage vs 'remote/hosted setups use create_session_link instead,' and new-assistant creation routed to create_assistant. This is direct alternative routing rather than leaving the choice to inference.

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