Add scoring doc, update readme

README.md

@@ -1,34 +1,34 @@
-# CHAOSS AI Detection Tool
+# CHAOSS AI disclosure detection
 
-A standalone CLI tool and GitHub Action that detects AI-generated contributions in git repositories. It works entirely from git-level data (commit emails, messages, trailers) using [go-git](https://github.com/go-git/go-git), with no platform API dependencies in the core. A separate text-scanning mode lets wrappers pipe in PR descriptions, issue comments, or any other text.
+A standalone CLI tool and GitHub Action that detects disclosed AI-generated contributions in git repositories. It works entirely from git-level data (commit emails, messages, trailers) using [go-git](https://github.com/go-git/go-git), with no platform API dependencies in the core. A separate text-scanning mode lets wrappers pipe in PR descriptions, issue comments, or any other text.
 
 The goal is to help open source maintainers understand when AI tools are involved in contributions, and to give community health projects like [CollectOSS](https://github.com/chaoss/collectoss/) and [GrimoireLab](https://github.com/chaoss/grimoirelab/) a way to track AI usage across repositories.
 
 ## What it detects
 
 The built-in detectors run against each commit, each producing findings at a confidence level:
 
-**High confidence** -- strong signals that an AI tool authored or co-authored the commit:
+- `Co-Authored-By` and `Assisted-By` trailers with known AI tool emails (Claude Code, Cursor, Aider).
+- Known commit trailers in formats unique to specific tools (such as Aider, EntireIO, Replit Agent/Assistant etc.) or footers (like `Generated with Claude Code`) that can contain values indicative of AI use.
 - Known AI bot committer emails (Claude, Copilot, Cursor, Codex, Gemini Code Assist, Amazon Q, Devin, Cline, Continue.dev, Cody, JetBrains AI, CodeRabbit). Also matches on the numeric prefix of GitHub noreply emails, so bot username renames don't break detection.
-- `Co-Authored-By` trailers with known AI tool emails (Claude Code, Cursor, Aider).
 - `git-ai` authorship logs stored in git notes under `refs/notes/ai`, including the attributed tool and model when available.
-- AI session ID trailers (such as Replit-Commit-Session-Id) combined with other known commit trailers, indicating that the commit was generated as part of an AI conversation or workflow.
-
-**Medium confidence** -- patterns in the commit message itself:
-- `aider:` prefix (Aider's default commit format).
-- `Generated with Claude Code` footer.
-- Known commit trailers in formats unique to specific tools (such as EntireIO, Replit Agent/Assistant) that can contain values indicative of AI use.
 - Branch names following conventions used by AI coding CLIs/agents (e.g. `codex/`, `claude/`, `cursor/`, `copilot/`, `devin/`, `cline/`, `aider/`, `gemini/`).
-
-
-**Low confidence** -- mentions of AI tool names in text:
-- Word-boundary matches for tool names like Claude, Copilot, Cursor, Aider, ChatGPT, Windsurf, Devin, etc. This detector also runs against commit messages, and is the primary detector for the text-scanning mode (PR bodies, comments).
+- AI session ID trailers (such as Replit-Commit-Session-Id) combined with other known commit trailers, indicating that the commit was generated as part of an AI conversation or workflow.
+- Mentions of tool names like Claude, Copilot, Cursor, Aider, ChatGPT, Windsurf, Devin, etc. This detector also runs against commit messages, and is the primary detector for the text-scanning mode (PR bodies, comments).
+- Disclosure of AI use from checkboxes in pull request description or comments, in text-scanning mode. Checkbox labels configurable by user.
 
 ## CLI usage
 
 ```
-disclosure scan [--range=BASE..HEAD] [--format=json|text] [--min-confidence=low|medium|high] [repo-path]
-disclosure text [--format=json|text] [--input=FILE|-]
+disclosure scan \
+	[--range=BASE..HEAD] [--format=json|text] \
+	[--min-confidence=low|medium|high] \
+	[--confidence-levels="low=30,medium=70,high=100"]
+	[repo-path]
+disclosure text \
+	[--format=json|text] [--input=FILE|-] \
+	[--checkbox-label-ai-used="AI was used"] \
+	[--checkbox-label-ai-not-used="AI was not used"]
 disclosure version
 ```
 
@@ -57,6 +57,11 @@ echo "I used Claude to write this PR" | disclosure text --format=json
 disclosure text --input=pr-body.txt
 ```
 
+### Numeric scoring
+
+Please see [SCORING.md](SCORING.md) for more information on disclosure's
+scoring methodology.
+
 ### Use as a CI gate
 
 The exit code makes it usable in shell pipelines and CI scripts:
@@ -181,6 +186,11 @@ cmd/                    CLI subcommands
 action/                 GitHub Action (composite action + labeling)
 ```
 
+## Other AI disclosure/attribution tools
+
+- [AItrributor](https://github.com/block/aittributor) - Prepare-commit-msg hook that adds AI agent attribution to git commits.
+- [Usagescale](https://usagescale.org/) - An open standard for declaring how a work was made, whose knowledge it carries, and who stands behind it.
+
 ## Contributing
 
 See [CONTRIBUTING.md](CONTRIBUTING.md).

SCORING.md

@@ -0,0 +1,45 @@
+# Disclosure numeric scoring (20th May 2026)
+
+Related issue: https://github.com/chaoss/ai-detection-action/issues/12
+
+## Simple additive scoring
+
+We use simple additive scoring per detector to compute the final score. Steps are as follows:
+1. Every detector produces one or more findings per commit.
+2. For every commit, the scoring is then grouped per-detector e.g. for commit C if there are two
+findings for detector `trailer`, one with score 35 and another with score 45, then `max()` is used
+to aggregate per detector findings at each commit. So in this case, commit C will have score 45 for
+detector type `trailer`.
+3. The per detector scores are then adds for each commit to get the score for a particular commit.
+e.g. if commit C gets per detector scores of 75.0 and 85.0 from detectors `trailer` and `toolmention`
+detectors respectively, then the total score for commit C will be 75 + 85 = 160.0
+4. Confidence is calculated at commit as well as finding level. It's based on the default confidence
+levels unless user-specified:
+- low confidence for score 0 to 30
+- medium confidence for score 31 to 70
+- high confidece for score 71 to 100
+
+### Example (branch feature/sample-commit)
+```git
+Author: Jon Snow <jon.snow@example.com>
+Date:   Sat May 17 11:42:08 2026 +0530
+
+feat(auth): add JWT refresh token rotation and session invalidation
+
+Implemented refresh token rotation for improved session security.
+Users now receive a new refresh token on every refresh request,
+and reused/expired tokens invalidate the session automatically.
+
+Co-authored-by: Claude <noreply@anthropic.com>
+```
+
+In above commit, scoring will be as follows:
+1. Trailer - Yes, one Co-Author finding, matches known trailer Claude Code (40) with known email (35) = 75.0
+2. Committer - No, committer email address doesn't match known AI bot email addresses = 0.0
+3. Branch - No, branch does not have known tools = 0.0
+4. Gitnotes - No gitnotes found = 0.0
+5. toolmention - Yes, one finding, tool Claude matched = 20.0
+
+**Total score: 75 + 0 + 0 + 0 + 20 = 95 pts**
+
+95 pts lies in 71 to 100 range, so it falls in confidence level here is **high**.