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

Annotations indicate readOnlyHint false and destructiveHint false. The description adds the key requirement and availability constraint, but omits the side effect of the 'new' parameter (invalidates previous share link) which is a potentially destructive behavior. Since annotations don't cover this, the description should have disclosed it. No contradiction, but a gap.

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?

Two sentences, front-loaded with the critical precondition, followed by the returns and key constraint. No fluff, efficient and scannable.

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 3-param tool with no output schema, the description covers the main flow (returns URLs, key requirement) but omits the 'new' parameter's effect on share links. It also doesn't state what happens if called prematurely, though the precondition implies it. The missing invalidation behavior is a notable gap for safe usage.

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 the baseline is 3. The description mentions 'Needs key' which echoes the schema's key description, adding no new meaning. It doesn't explain 'project' or 'new' beyond schema. So it adds no value beyond what the schema already provides.

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 the tool returns view_url and edit_url for a plan, with a clear precondition (after check_plan passes). It distinguishes from check_plan by being a follow-up, but it doesn't explicitly say 'opens a plan' or differentiate from show_plan. The purpose is clear enough for an agent to infer the action from the name and returns.

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?

Explicitly states when to call ('only after the last check_plan returned no issues') and gives a constraint ('Needs key; not available on beispiel-wohnzimmer'). It doesn't name alternatives or say when not to use, but the precondition is strong guidance.

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