Angel Number Lookup

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

Annotations already cover read-only and idempotent behavior, and the description adds useful behavioral detail: unindexed numbers fall back to numerological reduction. It also discloses that cost is plan-dependent and not in the public manifest. It does not describe return shape, but an output schema exists.

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?

The two prose sentences are front-loaded and efficient. The bracketed metadata adds useful endpoint and cost context but includes some redundancy, such as restating the required parameter already in the schema.

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 one-parameter lookup tool with annotations and an output schema, the description covers purpose, fallback behavior, and cost caveat adequately. The main remaining gap is routing guidance among the several angel-number siblings.

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 the schema itself says the number is digits-only and explains the unindexed fallback. The description adds only the word "sequence" and repeats the fallback, so it does not meaningfully extend parameter semantics beyond the schema.

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 states a specific verb and resource: "Look up the meaning of a specific angel number sequence," reinforced by the endpoint path with {number}. It does not explicitly distinguish this from angel-number siblings such as decode or the catalogue endpoint, so it stops short of 5.

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 phrase "specific angel number sequence" implies you call it when you already have a number to look up, but there is no explicit when-to-use guidance, no exclusions, and no naming of alternatives like the decode or catalogue tools. Usage is only implied.

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