Bibliomantic MCP Server

Look up a hexagram

get_hexagram

Read-only

Retrieve one hexagram’s full I Ching text by King Wen number (1–64), including judgment, image, and all six line statements for study or reflection.

Instructions

Return one hexagram's full text: judgment, image and all six line statements.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "number": "<number>"
    },
    "name": "get_hexagram"
  }
}

Input Schema

Name	Required	Description	Default
`number`	Yes	King Wen sequence number, 1 to 64.

Output Schema

Name	Required	Description
`name`	Yes	English name.
`image`	Yes
`lines`	Yes
`lower`	Yes	Lower trigram: lines 1 to 3.
`upper`	Yes	Upper trigram: lines 4 to 6.
`binary`	Yes	Bottom line first.
`number`	Yes	King Wen sequence number.
`pinyin`	Yes
`symbol`	Yes	Unicode hexagram character, U+4DC0 to U+4DFF.
`chinese`	Yes
`judgment`	Yes
`commentary`	No

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.1.0Oct 31, 2026

TDQS

A3.6/5.0

Behavior3/5

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

Annotations already declare readOnlyHint=true and openWorldHint=false, so safety and locality are known. The description adds the contents of the response, but with an output schema present that is largely redundant rather than adding behavioral context like error handling for out-of-range numbers.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

A single front-loaded sentence with no wasted words; the verb and the returned elements come immediately.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a one-parameter read tool with an output schema, the description covers enough for correct invocation. Only edge behavior (e.g., behavior at boundaries or unknown numbers) is left unstated, which is minor given the schema constraints.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% and the single `number` parameter is fully documented with its King Wen sequence semantics and 1-64 bounds. The description adds nothing beyond the schema, so the baseline 3 applies.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb (Return) and resource (one hexagram's full text), and enumerates the contents returned (judgment, image, six line statements). This is clearly distinguishable from cast_hexagram (drawing) and get_trigram (a different entity), though it does not name those siblings explicitly.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines3/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

Usage is only implied: the tool is for looking up a hexagram by number when you already know which one you want. There is no explicit statement of when to prefer this over cast_hexagram or how it relates to describe_method, so the agent must infer routing.

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

Deploy Server