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

Beyond the annotations (readOnly=false, destructive=false, idempotent=false), the description discloses several behavioral facts an agent could not infer: pinned facts from older projects are preserved, a new published version is created each call, permission level required, and no credit or language-model charge. 'Returns versionId and facts' partly overlaps the output schema but the rest is substantive.

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?

Five compact sentences, purpose front-loaded, then semantics, then constraints and cost. Slightly punchy rather than flowing, and 'Returns versionId and facts' duplicates what the output schema already states, but nothing is bloated.

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 mutation tool with full schema coverage, annotations and an output schema, the description covers purpose, side effects, permissions and cost adequately. It does not address what happens when baseVersionId is stale relative to the current version (a conflict/retry concern), which is the only notable gap.

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%, so artistId, baseVersionId and the facts array are already fully documented in the schema. The description's restatement of baseVersionId ('identifies the current version, or null when absent') adds no format or constraint detail beyond the schema text. Baseline 3 applies when the schema carries the parameter burden.

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 opening clause states a specific verb and resource ('Saves ... creative facts as a new published Artist DNA version') and scopes the input to customer-authored or approved facts. An agent can immediately distinguish this write tool from the sibling studio_artist_dna_read without opening either 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?

The description establishes the operating context: facts must be customer-authored or approved, the tool requires manager permission, and it costs nothing. 'Facts apply at once and need no pin' implicitly steers the agent away from the pinning path (studio_project_dna_pin) for new facts, but it never names an alternative or a when-not-to-use case explicitly.

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