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

Annotations only establish that this is a non-idempotent write with no open-world access. The description goes well beyond that by disclosing the return value (API key plus free trial credits), the irreversibility of the key ("cannot be shown again"), and that no email or browser is needed.

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 short sentences, each carrying a distinct fact: what it does, the precondition, and the handling obligation for the returned key. No filler, and the precondition is front-loaded before the storage instruction.

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 correctly explains what comes back and warns that the key is unrecoverable. The one missing detail is how the key is subsequently supplied on other calls, but for a two-optional-parameter creation tool this is close to complete.

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% and both parameters are marked optional with their own descriptions, so the schema already carries the semantics. The description adds nothing about name or contact, which is acceptable at full coverage but is the baseline rather than added value.

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 ("Create a new ogfetch account") plus the concrete output (an API key with free trial credits). The creation framing clearly separates it from sibling get_account, which reads an existing account.

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 an explicit precondition: "Only call this if you do not already have a key." That is a real when-to-use rule, though it does not name get_account as the alternative path for agents that already hold a key.

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