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

Annotations already cover read-only, idempotent, and non-destructive behavior. The description adds valuable behavioral detail: the name is discarded and never stored, the agent field is never required or verified, and master numbers are kept where the position allows. No contradiction with annotations.

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 description is compact and front-loaded with the most important information: what the tool computes. The HTTP endpoint line is slightly redundant for an MCP tool but is short and informative, so it does not meaningfully hurt conciseness.

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 read-only, four-parameter tool with complete schema coverage, the description explains both the computed outputs and the handling of optional inputs. While there is no output schema, the enumerated result list largely compensates; the main remaining gap is explicit guidance on choosing among sibling tools.

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 baseline is 3 even though the description adds little parameter-specific detail. It does add some semantic value by clarifying that omitting the name means name numbers are not guessed, and that the surname is used where the method requires the full name.

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 clearly identifies the resource as Pythagorean numerology and enumerates the exact outputs: Life Path, birthday number, and name-derived numbers. It distinguishes itself from sibling tools (bazi, zodiac, reading) by naming the specific numerological system and its components.

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 gives useful context about behavior with and without a name, but it never explicitly says when to choose this tool over siblings like asternym_bazi or asternym_reading. Usage is implied by the method name rather than stated.

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