layer_update

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

With no annotations, the description carries the full behavioral burden. It discloses the useful constraint that opacity is a percent 0..100 (beyond the schema's bare 'number'), but says nothing about partial-update semantics, whether omitted fields are left untouched, error behavior for bad layer_id, or session/auth requirements for this mutation.

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 tight sentences, zero filler, with the primary action front-loaded and the non-obvious opacity constraint immediately after. Every clause earns its place.

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?

An output schema exists, so return values need not be described. However, for an unannotated mutation tool with 0% schema coverage, the description is only marginally complete: it omits partial-update semantics, session requirements, and the meaning of the two required identifiers.

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%, so the description must compensate. It clarifies the meaning of three of five parameters (name=rename, visible, opacity) and adds the 0..100 range that the schema lacks, but leaves layer_id and session_id completely unexplained.

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 a specific verb+resource pair ('Rename a layer') plus the secondary operations ('set visibility/opacity'), so an agent knows exactly what mutation it performs. It is clearly distinct from layer_create and layer_delete in intent, though it doesn't explicitly name those siblings to route selection.

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?

There is no guidance on when to use this versus layer_create, layer_delete, layer_reorder, or transform_layer. No prerequisites (e.g. an active session or valid layer_id) are mentioned, leaving the agent to infer context entirely.

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