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

Annotations already indicate a non-read-only, non-idempotent, non-destructive write, so the description goes beyond them by explaining the registration effect, the requirement that the stats secret match the config hash, and the fact that a listed test can be removed from the dashboard while continuing to serve. It does not cover duplicate-registration behavior, but that gap is acceptable given the annotations and output schema.

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?

Every sentence earns its place: the first states the core purpose, the second gives precise usage conditions, the third references the preferred alternative, the fourth excludes keyless tests with reasoning, and the fifth notes a relevant behavioral nuance. It is information-dense without redundancy, and the most important facts are front-loaded.

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?

The description is complete for a three-parameter tool with a 100% schema, annotations, and an output schema. It covers when to use, the effect, the exclusion case, and post-registration behavior. Minor omissions such as error scenarios for mismatched secrets are not critical given the output schema handles return values.

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. The description adds meaningful constraint semantics by stating the stats secret 'must match the hash inside the config' and that the publishable key 'identifies the organization to register into,' which deepens the parameter explanations beyond the schema's descriptions.

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 opens with a clear, specific action: 'Registers a test you built earlier to the organization a publishable key belongs to,' and immediately explains the outcome (appears under My tests, dashboard-readable without the secret). It also distinguishes itself from the sibling build_test by explicitly noting that passing publishableKey there registers in one step. This leaves no ambiguity about what the tool does or how it relates to nearby tools.

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?

The description gives an explicit usage condition: 'Use this only when the user provides both the test's stats secret and a publishable key for an organization they administer.' It also names the alternative (build_test with publishableKey) and states a clear exclusion for keyless tests. This is textbook when-to-use guidance with no inference required.

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