add_luminance_adjustment

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

With no annotations provided, the description carries full burden. It explains that the adjustment only affects pixels within the specified brightness range, which is good. However, it does not disclose whether creating a new spot overwrites existing spots or if multiple spots can be added. The behavior regarding file modification (saving) is partially covered by the save_as parameter, but not explicitly stated.

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 well-structured with sections for adjustment_type, parameters, and luminance_range. It is somewhat verbose but front-loaded with the core purpose. Every sentence provides useful information, though some redundancy exists (e.g., repeating 'custom' context).

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?

Given the tool complexity (8 params, nested objects, no annotations), the description covers most key aspects. However, it lacks details on the transition, strength, spot_name, and save_as parameters, and does not explain the output schema referenced in the context. The behavioral aspect of whether multiple adjustments can be stacked is also 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?

The schema has 0% description coverage, so the description adds significant value. It details the valid values for adjustment_type (shadows, midtones, highlights, custom) with approximate luminance ranges, lists all parameter keys and their value ranges, and explains the structure of luminance_range for custom types. This goes well beyond the bare schema.

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 clearly states the tool adds a luminance-based local adjustment to a PP3 profile and explains that it creates a Locallab spot targeting a specific luminance range. While this distinguishes it from sibling tools like adjust_local_spot or apply_local_preset, it does not explicitly contrast with them, so a 4 is appropriate.

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 implies use cases such as shadow recovery or highlight compression, but it does not provide explicit guidance on when to use this tool versus alternatives like adjust_local_spot or apply_local_preset. It also lacks when-not-to-use instructions, so the guidance is only implicit.

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