launch

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

With no annotations present, the description carries the full burden and does disclose two important behaviors: the launched window is moved onto the agent's screen (a real side effect), and the call returns a snapshot. It omits failure behavior (unknown app, unopenable path) and any permission or security context for launching arbitrary executables, which keeps it short of a 5.

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?

Four tight sentences, front-loaded with the general capability and examples before the special "agent browser" mode and the side-effect/return notes. Dense and largely waste-free, though the opening enumeration list is slightly run-on.

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, no-annotation, no-output-schema tool, the description covers what to pass and what broadly happens. It is missing the two things an agent would most want for a launcher: error behavior and any constraint on what may be launched, leaving a noticeable gap given the absence of annotations.

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 0% and the single parameter "target" has no schema description, so the description must compensate — and it does, enumerating every accepted target form with examples plus the special "agent browser <url>" syntax. It stops short of 5 by not covering quoting, case sensitivity, or what happens when the target is not found.

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 ("Open") plus the full set of accepted resource types: app names, URLs, URIs, and file/folder paths, each with concrete examples ("Notepad", ms-settings:, chrome). An agent can immediately tell this is the entry point for starting anything, distinct from siblings like snapshot or window that operate on already-open windows.

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 implies when to use it (you need something opened) and adds one valuable routing hint: prefix with "agent browser <url>" for precise web control instead of a plain URL. However, it gives no explicit when-not-to-use guidance relative to siblings such as find or snapshot, so the agent must infer the boundary.

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