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

Goes well past the annotations (which only say non-read-only, idempotent, non-destructive) by disclosing that the server canonicalizes and computes the digest so the caller must not supply one, that identical bytes register once and return the same ids, that a malformed document returns recipe_invalid with exact failure pointers, and that registration builds nothing and costs nothing.

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?

Purpose and the critical 'don't state a digest' constraint are front-loaded, and most sentences carry distinct information (idempotency, error shape, next steps). It is dense and runs long, with a few sentences that could be tightened, but nothing is hollow filler.

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?

For a nested-object, no-output-schema tool, the description supplies the return field list (recipe_id, recipe_digest, dataset_id, table_id, source_ids), explains the ordering and one-id-per-source semantics of source_ids, and describes the failure mode. An agent has everything needed to call it correctly.

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 one parameter at 0% schema description coverage and an open-ended object schema, the description carries the burden: it shows the envelope shape ({recipe: {...whole recipe document...}}) and directs the agent to the recipe-reference resource for the inner fields. It does not enumerate the inner recipe keys itself, which is the one remaining gap.

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?

Opens with a specific verb+resource — 'Registers the JSON recipe' — and immediately defines what a recipe contains (provenance, shape, constraints). It is clearly distinguishable from the sibling read/inspect tools explain_recipe, forecast_recipe and test_recipe, which the description names separately.

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?

Explicit ordering is given: read mostlyright://recipe-reference and mostlyright://recipes/examples before writing, check with explain_recipe first, then forecast_recipe/test_recipe for paging or per-row sources, then start_run with recipe_id and recipe_digest. When-to-use and when-to-consult-alternatives are both spelled out.

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