Create DataLens key for embedding

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

Goes well beyond the annotations by disclosing a critical behavioral trait: the private key is returned only once and never again by get/list, and it enters the agent's context. This is exactly the kind of non-obvious, security-relevant behavior that annotations (readOnlyHint/openWorldHint/idempotentHint) cannot convey.

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?

Two sentences, zero filler. The purpose and return value are front-loaded, and the key-handling warning follows immediately after.

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?

There is no output schema, so the description must explain return values — and it does (id and private key). Combined with the handling instructions, an agent has everything needed to call this safely and 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?

Schema description coverage is 100% (title and workbook_id are both documented), so the schema already carries parameter meaning. The description adds nothing about parameter formats or constraints, so the baseline 3 applies.

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 key for embedding') and names exactly what it returns ('its id and its private key'). It also implicitly distinguishes itself from the sibling read tools by noting that embeddingsecrets_get/list do not return the private key.

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?

Gives operational context for using the tool's output ('hand it to the person at once, and do not repeat it in later messages'), which is real usage guidance. It does not, however, explicitly state when to prefer this over alternatives like datalens_embeds_create or the other secrets tools beyond the one negative note.

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