design_apply_posterize

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

With no annotations, the description must carry the behavioral burden, but it only says the tool adds a layer and reduces color levels. It does not mention whether the operation is destructive, how the layer is inserted, undo behavior, or any permission requirements for a mutation tool.

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?

The description is a single efficient sentence that front-loads the main action and effect. It is concise with no wasted words, though it could arguably include a brief usage qualifier without becoming 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?

For a simple two-parameter filter tool with no output schema and no annotations, the description covers the core action and the schema covers the parameters. However, it omits usage context and behavioral details that would help an agent choose it among the many filter siblings.

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 100%, so the parameters 'levels' and 'intensity' are already fully documented in the schema. The description adds no further meaning beyond the high-level effect, so the baseline score 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 states a specific verb+resource (add a posterize filter layer) and the effect (reduces color levels), so an agent can identify what it does. It does not explicitly distinguish itself from similar filter siblings such as design_apply_threshold or design_apply_dither, which keeps it from a 5.

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 gives no explicit guidance on when to use this filter instead of alternatives like threshold or dither, nor does it state prerequisites or exclusions. Usage is only implied by the phrase 'add a posterize filter layer.'

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