update_icon

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

Annotations already indicate a non-read-only, non-destructive mutation. The description adds useful behavioral detail beyond that: the original icon is preserved, and a revision must be supplied. This helps an agent understand the concurrency-oriented intent of expectedRevision.

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?

Three short sentences, no fluff, and the core purpose is front-loaded. Every sentence contributes either to what the tool does, the required workflow, or the key behavior that the original is preserved.

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?

The description covers the key workflow, the full-spec nature of the input, and the preservation guarantee. It does not discuss failure cases like revision mismatches or duplicate output names, but the schema and required fields carry much of the structural burden. Overall enough for correct invocation.

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 0%, so the description must compensate. It effectively explains all four parameters: name via 'Read the icon first', outputName via 'under a NEW name', expectedRevision via 'supply its revision', and spec via 'revised complete specification' and 'Change layers, materials, positions, fills or appearances in spec.'

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 operation: save a revised complete specification under a new name, while preserving the original. It clearly distinguishes itself from create_icon by requiring reading an existing icon first and from read_icon by being a write operation.

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?

It gives an explicit precondition: 'Read the icon first and supply its revision.' This tells an agent the required workflow. It does not explicitly name alternative tools or state when not to use it, but the intended context is clear enough.

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