compose

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

With no annotations, the description carries the full burden of behavioral disclosure. It states the action but does not reveal whether this is a read-only render, a state-changing operation, or what the return value is. No mention of side effects, resource persistence, or output format.

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 two sentences long, front-loaded with the primary purpose, and contains no filler or redundant details. Every sentence earns its place.

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?

The tool has 5 parameters including a complex layers array, but the description does not explain what the output of composition is (e.g., a scene ID, image data) since there is no output schema. It also omits crucial context like coordinate system origin, whether layers are composited back-to-front (though schema mentions it), or how this tool fits into a workflow with siblings like 'export' or 'create'.

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 covers all parameters with descriptions (100% coverage), so the baseline is 3. The description adds minimal information beyond the schema, only reinforcing the x/y placement concept. No additional insight on scale, palette, or layer ordering beyond what schema already provides.

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 a specific verb ('Compose') and resource ('multiple sprites into a single scene'), with explicit mention of placing sprites at x,y positions. This differentiates it from sibling tools like 'spritesheet' or 'tilemap' that have different outputs.

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 usage (when you need to assemble sprites into a scene) but provides no explicit when-to-use guidance or mention of alternatives. There are no exclusions or prerequisites stated.

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