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

Annotations declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false. The description adds the key disclosure behind the name would otherwise obscure: it 'opens nothing by itself' and returns procedural instructions. That resolves the read-only nature in terms of user intent. Minor value-add detail: the note about no official MCP server explains why a browser-driven path is needed.

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 definition is lightly padded. The trailing API discussion, including the odd 'checked 17 Oct 2026' timestamp, is mostly background justification. The most decision-relevant caveat ('opens nothing by itself') is buried mid-sentence rather than front-loaded, so an agent skimming may misread the tool as performing the upload.

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 zero-parameter, read-only instructional tool with no output schema, the description adequately covers output shape (step-by-step screens, buttons, fields) and the next action step. It could better specify prerequisites, such as which file or account state is assumed. Overall it is complete enough to invoke correctly.

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 tool takes zero parameters, so schema semantics carry no burden. The baseline of 4 is appropriate, and the description needs no parameter explanation.

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 and resource and clarifies the crucial nuance that the tool does not itself upload but 'Returns how to do it in Printful step by step (screens, buttons, fields)'. The opening phrase 'Upload design file in the user's own Printful account' initially reads like a write action, but the clarification corrects this. It is clear enough to distinguish from the actual action tools (cotlet_browser_*).

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?

Explicit follow-through guidance is given: after getting instructions, 'then do it with the cotlet_browser_* tools in the user's Printful Cloud Browser.' It also rules out waiting for an official MCP API path. It does not say when to prefer this over other upload-related siblings such as cotlet_upload_file or cotlet_app_guide, which is a minor gap.

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