Split or merge walls

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

Annotations only flag destructiveHint=true and readOnlyHint=false; the description goes far beyond by disclosing exactly what survives (longest wall keeps id, thickness, height, type, finishes), what is destroyed (other walls deleted), what is preserved (doors and windows), that gaps are closed, and what the reply returns. This is unusually rich behavioral disclosure for a destructive edit.

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?

Front-loaded with the two operations, then dense mode-specific detail. The middle sentence is long but each clause carries operative information (id retention, build preservation, deletion, openings, gap closing), so little is wasted.

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, the description needn't detail return structure, yet it still notes the reply names resulting ids. Combined with full parameter coverage and the destructive-behavior explanation, nothing an agent needs to invoke this correctly is missing.

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, but the description adds real meaning: t's 0..1 range and default 0.5 within the split action, and that ids for merge are ordered along the line they make. It does not restate id/action, but the added mode-specific semantics lift it above 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?

States a specific verb pair and resource: 'Split a wall in two, or join walls into one.' No sibling tool competes for wall geometry, so an agent can route here unambiguously from the name plus first sentence.

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?

Explains the two modes and gives concrete merge scenarios (a wall a partition interrupted, a stretch imported as many segments, the same wall drawn twice), which tells the agent when merge is appropriate. It stops short of stating when NOT to use the tool or naming an alternative, so it does not reach 5.

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