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

Adds real behavior beyond annotations: newest-first ordering, the exact fields returned per canvas (name, card count, last update, id), and cost/free-ness. "Read-only" largely restates readOnlyHint=true, so it earns a 4 rather than a 5, but the ordering and per-item payload disclosure are genuine value.

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?

Two sentences, front-loaded with the verb and ordering, then the usage routing. The middle clause defining canvases is slightly verbose but justifies itself by grounding an unfamiliar product concept.

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?

No output schema exists, but the description compensates by enumerating the returned fields. With only two well-documented optional params and annotations covering the safety profile, nothing an agent needs to call this correctly is 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?

Schema description coverage is 100%, so limit (1–50, default 20) and search are already fully documented. The description says nothing about either parameter — no hint that search matches names or how limit interacts with result ordering — so baseline 3 applies.

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?

Specific verb + resource ("List the user's PopNow canvases") plus a concrete definition of what a canvas is (boards with pictures, videos, notes and shots) and the ordering (newest first). It also implicitly separates itself from get_canvas by framing this as the discovery step.

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?

Explicitly states the workflow role: "Use it to find the canvas the user means before get_canvas or add_to_canvas." That names both alternatives and the condition that selects them, so an agent knows this is the lookup-first tool.

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