git:20260906.0d1fa42 to git:20260906.f99ce94

6 added, 6 removed. Audit A to A.

---

name: license

description: Decide what may be carried over from a prey repository under its license. Modes are COPY, COPY_FILE, REIMPLEMENT, IDEAS_ONLY and HUMAN. Use when a nutrient's license mode is unclear, when asked whether code or configs from another repository may be copied, or when a sniff verdict says HUMAN.

---

# License rules

The verdict is produced by a deterministic engine (`crab sniff`, `license.json` in a digest).

Your job is to apply the mode, explain it, and stop when the engine says `HUMAN`.

## Modes

| Mode | Allowed | Required |

|---|---|---|

| `COPY` | copy code, configs and text | keep the copyright notice; record the source in `THIRD_PARTY_NOTICES.md`; Apache-2.0 also needs the NOTICE file carried over |

- | `COPY_FILE` | copy whole files (MPL-2.0, EPL, CC-BY-SA documents) | the file keeps its own license header; do not merge it into files under the host license |

- | `REIMPLEMENT` | use the prey as a specification | clean room: a spec without code, then an implementer without access to the prey (the `crab-cleanroom-impl` subagent from 0.3); record "implemented from a specification" in the provenance |

+ | `COPY_FILE` | copy whole files (MPL-2.0, EPL, CC-BY-SA documents) | the file keeps its own license header; do not merge it into files under the maw license |

+ | `REIMPLEMENT` | use the prey as a specification | clean room: a spec without code, then an implementer without access to the prey (the `crab-cleanroom-impl` subagent from 0.3); record "implemented from a specification" in the trace |

| `IDEAS_ONLY` | ideas, architecture, approaches, facts | not a line of code, configuration or documentation text |

| `HUMAN` | nothing yet | a person decides; present the evidence (`license.json`: files, manifests, headers, conflicts) |

## Rules that override the matrix

1. Issue, discussion and pull-request comment text is always `IDEAS_ONLY`: the copyright belongs

to the commenters. Carry over the need and a link, not the text.

2. Configuration files and small snippets are not automatically free: same mode as code.

- 3. A host in `strict` mode (`.crab.yml`) downgrades `COPY` to `REIMPLEMENT` for code; only configs

+ 3. A maw in `strict` mode (`.crab.yml`) downgrades `COPY` to `REIMPLEMENT` for code; only configs

and templates are copied.

4. Per-file exceptions in `license.json` (vendored directories, headers with another SPDX id)

override the repository license for those files.

5. A conflict between the LICENSE file and a manifest, or no license at all, is `HUMAN`.

## How to compute a mode

- - `crab sniff <prey> --host .` prints the mode for this host.

- - `license.json` in the prey digest has `modes_by_host_class` (permissive, gpl, proprietary hosts)

- and `verdict` when a host license was known at digest time.

+ - `crab sniff <prey> --maw .` prints the mode for this maw.

+ - `license.json` in the prey digest has `modes_by_maw_class` (permissive, gpl, proprietary maws)

+ and `verdict` when a maw license was known at digest time.

- The full matrix is in `references/matrix.md`.

This is a compliance aid, not legal advice; say so when the user asks about an edge case.