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

Annotations only mark this as non-readOnly/non-destructive/non-idempotent, which is ambiguous for a dual list/create tool; the description resolves that by stating list is the default read and create is the mutating branch that returns a project_id. It further discloses auto-filing behavior and that a missing project_name is silently created — real behavioral context beyond the annotations.

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 action semantics are front-loaded and every clause carries information (returned fields, filing behavior, cross-tool routing). It runs long in a single dense block, but no sentence is filler and the ordering follows the agent's decision sequence.

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?

With no output schema, the description carries the return-value burden and does so: list returns id, title, asset count and the active project; create returns project_id. Nothing critical for correct invocation 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%, with both the action enum and the title requirement already documented in the schema. The description restates the create/title dependency rather than adding format or validation detail, so 3 is the appropriate baseline when 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?

States a concrete verb pair and resource ('List or create the user's Popcraft projects — the folders their generations are organized into'), and the gloss clarifies the entity precisely against siblings like popcraft_show_generations and popcraft_show_medias. An agent can tell what this tool owns without opening the schema.

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?

Ends with explicit routing ('Use this tool when the user asks to see, organize into, or start a new project') and names the downstream alternatives (popcraft_generate_image/video/audio) plus the condition that selects them. It also documents the fallback that a non-existent project_name is auto-created, removing a common inference gap.

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