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

No annotations exist, so the description carries the full burden. It does disclose the return shape (0-100 score, label, reasons) and the underlying computation basis (life path and mulank), which is useful. It omits error behavior for invalid dates, whether the result is symmetric for (A,B) vs (B,A), and whether the score is deterministic.

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 compact sentences plus an example input; the output contract is front-loaded and nothing is wasted. The example earns its place by resolving format ambiguity in one line.

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 supplies the return value shape itself, so an agent knows what comes back. It lacks only edge-case guidance (invalid dates, symmetry) for a two-parameter tool that is otherwise fully specified.

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%, so the schema already documents dobA and dobB with format and pattern. The description reinforces the YYYY-MM-DD format and adds a concrete worked example, which is a modest value-add over 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?

States a specific operation: takes two birth dates and returns a harmony score with label and reasons derived from life path and mulank. This implicitly distinguishes it from the single-person sibling tools (lifePath, loShuGrid, nameNumber) by being the pairwise comparison, though it never names them explicitly.

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?

Usage is only implied by the two-person input shape; there is no explicit statement of when to use this versus the sibling numerology tools or any exclusions. An agent can infer it's for relationship/partner matching but the description doesn't confirm that.

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