ensure_project

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

Annotations already declare idempotentHint=true, readOnlyHint=false and destructiveHint=false; the description goes further by explaining the mechanism behind idempotency (same repository path returns the existing project), the fields returned (id, slug, human_key, created_at), and the NOT_FOUND failure mode of dependent tools. Only auth/permission requirements are unaddressed, which is a minor gap for a local project-registration call.

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?

Three compact sentences, each carrying distinct information (scope, idempotency rule, dependency/alternatives), with the primary action front-loaded. Nothing is redundant padding.

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 compensates by naming the returned fields, and it covers the state-dependency and idempotency behavior an agent needs before calling. There is no meaningful gap for a one-parameter, non-destructive tool.

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?

With a single parameter and 100% schema description coverage, the baseline is 3, but the description adds meaning beyond the schema by tying human_key to project identity semantics: repeating the same repository path returns the existing project rather than creating a duplicate. It stops short of restating the absolute-path formatting constraint already documented in the schema.

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 ('Create a project without registering an agent') and immediately distinguishes itself from the two siblings that also create projects, register_agent and macro_start_session. An agent can tell exactly what this tool is and is not without opening a 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?

It explains when to reach for this tool (you want a project without registering an agent), when the call is redundant (register_agent and macro_start_session create it themselves), and the prerequisite consequence of skipping it (other tools fail with NOT_FOUND). That is explicit when/when-not/alternative guidance.

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