upscale_image

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It mentions quality preservation, which is useful, but fails to disclose critical traits like whether this is a read-only or mutating operation, potential costs, rate limits, authentication needs, or output format (e.g., URL, file). For a tool with no annotation coverage, this is a significant gap.

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 appropriately sized with two concise sentences that are front-loaded with the core purpose. Every sentence earns its place by stating the action and providing usage context without any redundant or verbose language.

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's moderate complexity (3 parameters, no output schema, no annotations), the description is minimally adequate. It covers the basic purpose and usage but lacks completeness in behavioral traits (e.g., mutation effects, costs) and output details, which are crucial for an agent to use it correctly without structured output guidance.

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 description coverage is 100%, so the schema already documents all three parameters thoroughly (e.g., 'image_url' with upload guidance, 'scale' with enum values, 'model' with options). The description adds no additional parameter semantics beyond what's in the schema, making the baseline score of 3 appropriate as the schema does the heavy lifting.

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's purpose with specific verbs ('upscale', 'enhancing') and resources ('image', 'resolution'), and distinguishes it from some siblings like 'resize_image' by emphasizing quality preservation. However, it doesn't explicitly differentiate from all potential alternatives like 'edit_image' or 'generate_image_from_image' for enhancement tasks.

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 provides implied usage guidance ('Use for enhancing low-resolution images'), which gives a general context. However, it lacks explicit when-not-to-use scenarios, prerequisites (e.g., file size limits), or named alternatives among siblings (e.g., when to choose 'resize_image' vs. this tool), leaving some ambiguity for the agent.

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