photoshop_feather_selection

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

With no annotations, the description carries full burden and succeeds: it lists preconditions (active document and active pixel selection), side effects (modifies selection edges), and even the return JSON shape. No contradictions.

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?

Every sentence is purposeful and the description is front-loaded with the definition. The use/when-not/returns/preconditions/side-effects structure packs a lot of actionable information into a compact form.

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 2-parameter tool with no output schema, this description covers the action, usage criteria, return shape, preconditions, and side effects. Nothing an agent needs to decide on or invoke the tool 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% and both parameters already have meaningful descriptions (radius minimum, optional document_id with use-case). The tool description adds no extra parameter semantics, so the baseline of 3 is appropriate.

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 opens with a specific verb-resource pair: 'Feather (soften) the edges of the active pixel selection', which precisely states the action and scope. This differentiates it from siblings like expand/contract selection and image blur operations.

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?

Explicit 'Use when' and 'Do NOT use when' conditions are given ('soft transitions before fill, mask, or delete operations' vs 'hard edge is required or no selection exists'). This gives the agent concrete decision criteria, even though no alternative sibling is named.

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