upscale_image

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

With no annotations provided, the description must disclose behavioral traits. It mentions the provider key requirement but omits output location, side effects (e.g., writes new file vs overwrites), error handling, or whether the operation is destructive. This is a significant gap 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, focused sentence that front-loads the core purpose and scale options. No redundant information; efficient and well-structured.

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 tool with no annotations and no output schema, the description is incomplete: it does not specify what the tool returns (e.g., output file path), nor does it address potential limitations or preconditions beyond the provider key. An agent calling this tool would lack critical operational details.

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 already documents all parameters with 100% coverage. The description adds minimal semantic value beyond restating the scale and provider enums and the key requirement; it does not explain parameter nuances beyond the 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?

Clearly states the action (upscale) and resource (image), specifies scale factors (2x/4x) and providers (Replicate Real-ESRGAN/fal), distinguishing it from sibling resize_image and other image tools. The mention of AI providers signals a specialized upscaling capability.

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 the tool is for AI-based upscaling and mentions the provider key requirement, but does not explicitly contrast with alternatives like resize_image or state when not to use it. No exclusion criteria are given.

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