# ADR-011: Config as Module entry with Literal values

## Status

Accepted

## Context

Graph type configurations can be general (any valid config at construction time) or specific (frozen values for a particular graph type). The Module format needs to express both.

## Decision

The general `Metagraph.Config` uses `Type.Union` with defaults for construction-time validation ("any valid config"). Specific graph types freeze config values to `Type.Literal`, making the config a precise contract rather than a validation surface.

Construction flow: consumer provides a general config → validated against `Metagraph.Config` → the specific graph type Module freezes the values with `Type.Literal`.

## Consequences

- `Metagraph.Config` accepts `{ type: "directed" | "undirected" | "mixed", multi: boolean, allowSelfLoops: boolean }` with defaults
- `CallGraph.Config` is `{ type: "directed", multi: false, allowSelfLoops: false }` — frozen, no ambiguity
- Type narrowing from Union to Literal is explicit in the Module, no builder step needed

## References

- [metagraph-module.md](../metagraph-module.md)