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

Goes well past the annotations by disclosing cost behavior ('nothing charged'), the empty initial state, the concrete stack and file layout for each kind, the ADMIN_PASSWORD-protected owner pages, and an explicit constraint not to edit site/vendor/. It also states what is returned (project id, studio link, starter files), which is significant since no output schema exists.

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?

Front-loads the core action and cost/state guarantee in the first clause, then enumerates the three kinds in a parallel, scannable structure. The per-kind stack detail is long but earns its place by driving the enum decision; only minor trimming would be possible.

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 supplies the return contract (project id, studio link for preview/publish/export, starter files), covers both parameters, and flags the vendor-directory constraint. Nothing needed to invoke it correctly or interpret the result 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 coverage is 100%, so the baseline is 3, but the description materially expands the 'kind' enum by describing what each starter actually contains (Next.js 15 + Fastify + Postgres vs plain HTML vs Phaser/Three.js in site/vendor). That lets the agent choose a kind without guessing at the schema's one-line enum labels.

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 specific verb and resource ('Make a new SPOE project from SPOE's starter') plus the resulting state ('nothing built yet'), and names the follow-up tool (write_files) so the agent knows what this tool is for. It is clearly distinct from the create_app sibling by being an empty starter scaffold rather than an app deployment.

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 positions the tool as the starting point for authoring ('for you to write with write_files'), which tells the agent the workflow context. It does not, however, say when to prefer this over create_app or list_apps, so the sibling differentiation is implicit rather than stated.

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