gimp_modify_selection

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

Annotations already declare destructiveHint=false and openWorldHint=false, so the safety profile is partly covered. The description adds real behavioral meaning beyond that: units (px) for grow/shrink/border, feather radius, and that sharpen removes blur — but it does not say what happens when no selection exists or whether the modification applies to the whole layer.

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?

A single tight sentence with the operation list front-loaded after the verb; nothing is padded. It is terse to the point that it drops potentially useful clauses, but it is not bloated.

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 no output schema and a mutation that touches the current selection, the description covers the operations and their units but omits image_id, the default amount, and what happens absent a selection. Adequate but with clear holes for a 3-parameter write tool.

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 names the five 'action' values and gives units for 'amount' (px for grow/shrink/border, radius for feather), which is genuine added meaning. The third parameter, image_id, is never mentioned, and the default amount of 5 is not explained.

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?

Specific verb ('Modifica') + resource ('la selección actual') plus an enumeration of the five operations it performs. An agent can tell it acts on the selection rather than building one, but the description never contrasts it with gimp_select or gimp_stroke_selection, which operate on the same resource.

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?

No statement of when to use this tool versus the selection-related siblings (gimp_select, gimp_select_by_color, gimp_stroke_selection), nor any prerequisite such as an active selection existing. The action list implies usage but gives no selection conditions.

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