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

Annotations already declare readOnlyHint=false, destructiveHint=true, openWorldHint=true, and idempotentHint=false, so the safety profile is structured. The description adds genuinely useful context beyond them: execution is shell-free ('no shell parsing'), and launching can execute code and change desktop state. It does not discuss permissions/auth or failure modes, but the annotation layer carries much of that 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?

Three sentences, no waste, and the usage trigger is front-loaded before the sibling disambiguation. Slightly dense with three tools and a behavior clause packed in, but every sentence carries 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?

With an output schema present, return values need not be described, and the description covers the trigger, the alternatives, and the mutation risk of a destructive, non-idempotent launch. The only thin spot is that required device pairing is only implied by 'paired computer' rather than stated as a precondition.

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 100%, so all seven parameters including app/path aliasing, args array, cwd, and the wait_for_window/wait_timeout_ms pair are already documented in the schema. The description echoes the no-shell argument semantics but adds no new parameter-level detail. Baseline 3 is correct.

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?

States a specific verb and resource ('start a named desktop application or permitted executable on a paired computer') and explicitly delineates itself from two siblings, start_process and open_path. An agent can distinguish this tool's scope without opening any schema.

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?

Gives an explicit trigger condition ('when the user explicitly asks to start a named desktop application'), and names both alternatives with their differing scope: start_process for shell commands/scripts, open_path for existing files/directories. Routing is unambiguous.

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