editor_ensure

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

With no annotations to fall back on, the description discloses meaningful behavior: it may open a browser, it blocks/waits for a connection, and it does not create store directories. However, it omits details such as timeout behavior, side effects of launching a browser, or what 'connected' means, so transparency is only partial.

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?

One sentence with an active verb, immediately states the action and wait condition, plus a useful explicit non-effect. No filler or redundancy.

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 zero-parameter setup tool, the description covers what the tool does, the environment it affects, and an explicit non-effect. It lacks timeout/failure details, but the schema and parameter surface are minimal, so this is reasonably complete.

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?

The tool has zero parameters and schema coverage is complete, so the baseline of 4 applies. The description does not need to explain parameters.

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 a specific action ('Open the local draw.io canvas') and an outcome ('wait until it is connected'), which is distinct from all sibling diagram_* tools that perform modifications or reads on diagrams. The negative claim 'does not create store directories' also helps disambiguate scope.

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?

While 'if needed' implies this is a setup or prerequisite step, the description provides no explicit guidance about when to call this tool versus alternatives, nor any conditions under which it should be skipped.

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