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

Annotations already declare it as a non-read-only, non-idempotent mutation. The description adds real value beyond that by stating that expectedSpecVersion exists to prevent stale writes, which is a behavioral concurrency contract not encoded anywhere in the structured fields. It stops short of saying what happens on a version mismatch or whether unspecified bounds are preserved.

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 short sentences: the action first, the critical precondition second. Nothing redundant, no filler.

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 mutation with a nested input object and no output schema, the definition leaves meaningful questions open: whether omitted minZoom/maxZoom reset to the documented defaults (0/22) or preserve existing values, and how a stale expectedSpecVersion surfaces to the caller. Annotations cover the safety profile, so this is adequate but with clear gaps.

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?

Top-level schema coverage is 0%, so the description must carry the load, and it does for the one genuinely non-obvious parameter by explaining expectedSpecVersion's anti-stale-write purpose. The nested input properties (layerId, title, minZoom, maxZoom) are already documented in the schema, so the remaining unmentioned projectId is a minor gap.

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: setting a layer's minimum and maximum visible zoom levels. This is concrete enough to distinguish it from siblings like project_set_layer_visibility or project_set_layer_filter, though it never names those alternatives explicitly.

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 usage (editing a layer's zoom visibility window) and explains the concurrency precondition for expectedSpecVersion, but gives no explicit when-to-use/when-not guidance or pointers to sibling tools such as project_update_layer_style.

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