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spawn_child_chain

Destructive

Fork a chain to create a child when work needs a different type, requiring a spawn reason to make cross-domain patterns researchable. The parent keeps its type and history.

Instructions

Fork a chain when work needs a different type (Decision 5).

    Type changes create child chains; parent retains its type and
    history. spawn_reason is required — it's what makes cross-domain
    ideation patterns researchable.

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": {
      "params": "<params>"
    },
    "name": "spawn_child_chain"
  }
}

Input Schema

Name	Required	Description	Default
`params`	Yes

Output Schema

Name	Required	Description	Default
`result`	Yes

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.2.1Sep 13, 2026

TDQS

A3.9/5.0

Behavior4/5

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

Annotations already declare the mutation profile (destructive=true, idempotent=false, readOnly=false). The description adds genuine behavioral context beyond that: the parent retains its type and history, and the operation is explicitly 'fork, never morph'. It stops short of describing creation side effects or reversibility.

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

Conciseness4/5

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

Three tight sentences, front-loaded with the action and its trigger. The '(Decision 5)' reference occupies space without helping an agent decide or call the tool, but nothing else is wasted.

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?

An output schema exists, so return values need not be explained. The description covers trigger, fork semantics, and the required reason field. The remaining gap is sibling disambiguation from branch_chain, which matters given the crowded sibling set.

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?

Reported schema coverage is 0% for the top-level schema, though the nested $defs carry per-field descriptions. The description adds meaning only for spawn_reason (required, and why), ignoring parent_chain_id, chain_type, title, and completion_vision. Marginal added value keeps this at baseline.

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 (fork/spawn) and resource (chain) plus the triggering condition: work needing a different type. The fork-vs-morph semantics are clear. It does not, however, distinguish itself from the sibling branch_chain, leaving the agent to infer the boundary.

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

Usage Guidelines4/5

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

Gives a clear trigger: 'when work needs a different type (Decision 5)'. This tells the agent when the tool is appropriate. It names no alternatives or exclusions, so a reader can't tell how it relates to branch_chain or create_chain from the description alone.

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