📄 README.md

Equalify Iris

Image-to-Accessible-HTML parsing service. Iris converts a sequential set of image files (e.g. the rendered pages of a PDF) into a single content-only, WCAG 2.2 AA accessible HTML document: one vision call per page against a prompt anyone can improve, then an iterative reader/copy-editor review loop over the assembled document.

Three constraints shape the whole design, and the code is written to hold them:

Content only. No CSS, no visual fidelity, no pixel-perfect layout. A two-column source

becomes linear semantic HTML. WCAG 2.2 AA is the fixed target and is not a per-run option.

One machine, no vendor lock-in. A laptop, a Mac Mini or a self-hosted box are all

first-class targets, with no AWS/GCP/Azure account required. Every external dependency — model provider, database, object store — is replaceable by configuration, and the defaults (SQLite + local filesystem) need nothing hosted. That is also why in-process work is budgeted rather than assumed: see the concurrency and request-limit knobs below.

GitHub, deliberately not replaceable. GitHub is the only sign-in, and a token is

required on every call, because that token is what files each session's contributions under the user's own name. There is no anonymous mode and no opt-out — why.

How it works

The pipeline as implemented today runs in three phases:

Extraction — for each page image, the page agent (agents/page.md) converts the whole

page to an accessible HTML fragment in one vision call. The output is then verified, and corrected if the verifier objects. If the page agent names a content type a specialist would handle better, that specialist is dispatched and its output merged. Pages are independent, so they are extracted in parallel — up to defaults.extraction_concurrency at a time (default 5, clamped to 1..16). Fragments keep submitted document order regardless of which page finishes first; lower it if your provider rate-limits you, or set 1 for fully serial. Across sessions, defaults.max_concurrent_runs (default 2, clamped to 1..32) bounds how many runs execute at once; further uploads wait in status: "queued" rather than being rejected.

Assembly — fragments are joined in page order into a minimal accessible document shell

(<html lang>, <title>, <main>) and validated with axe-core.

Review — the Reader reads the document in chunks as two views (HTML + a flattened

screen-reader view) and flags reading-order / semantic / accessibility issues, attributing each to the source page(s) it appears on; the Copy Editor proposes fixes against **just those pages'** source images; fixes are applied and the document re-linted. Loops up to max_review_iterations (default 3) — or until a round changes nothing, since an editor that answers and hands back the document it was given would answer the same way next round. A document that spans several chunks is read in parallel — the chunks are independent calls over one unchanging body — up to the same defaults.extraction_concurrency at a time, and the issues they raise stay in chunk order.

When Iris meets content a specialist agent would handle better than the general pass, it drafts that agent and automatically files a GitHub issue titled New agent suggestion: <type> (with the agent code + context) on the upstream repo. Maintainers triage those issues; merged agents become part of the shared agents/ library. (An earlier design forked the repo and opened a PR when the session closed; nothing forks now — see design notes.)

Those issues are identified by their title prefix, not by a label, and deliberately so: GitHub silently drops labels set by anyone without push access to the repo, which is most of the people this is built for. A label would therefore have been missing on exactly the issues that most needed it, with nothing to say so — and the duplicate check that filtered on it would have refiled the same suggestion every session, under a different person's name each time. If you want labels on these, add a repository rule keyed on the title prefix; it applies them as the repo rather than as the filer, so it works no matter who filed.

Terms

Five words in this repo mean something narrower than they do in ordinary English. Every document here uses them in the senses below. **Every one of the five also carries at least one unrelated sense**, listed with it, and the text has to say which it means.

fragment — one page's extracted HTML, plus the record of where it came from. A fragment

carries the source page image, the page's position in the submitted document, which agent produced it, the agent's own log line, and any edges where content looked cut off (Fragment in src/pipeline/fragment.ts). Assembly joins fragments in that order; it does not re-read pages. Two unrelated uses: a URL fragment identifier, the #id a link points at, which is what docs/API.md's links_unresolved_rate is about; and an issue-<n> **fragment of a branch name** in docs/ci.md.

block — one top-level element of the assembled document, with everything nested inside it. The

document is normally shown to the Copy Editor with a  comment above each one, and the editor replies with replacements for the blocks it wants to change rather than with a new document. A document too long to correct in one reply is instead cut at those same boundaries into sections, and a section request carries no @block markers and is answered whole (EDITOR_SYSTEM and EDITOR_SECTION_SYSTEM in src/pipeline/review.ts). Three unrelated uses: a mapping in the config file — the providers block, the bedrock block; a run: block in a GitHub Actions workflow; and a group of table rows, as in docs/models.md's "once per corrector block" and docs/cost.md's "those three blocks".

verdict — the Feedback Agent's decision about one page: two booleans, faithful and

accessible, plus the problems it lists. Both booleans have to be there. A reply missing either one is not a verdict on that page and is not counted as one (VerifyOutput in src/pipeline/feedback.ts). One unrelated use, in CONTRIBUTING.md and docs/ci.md: a CI session's structured output — the review bot's advisory decision about a pull request, and the triage session's about an issue. That is about your repository rather than about a page.

declaration — the page agent's answer that a page holds no content. It is a claim, not an

absence. The agent asserts blankness with "blank": true or says so in its log, and the pipeline can refuse the claim: a page too dark to read is not a blank page (blankDeclaration in src/pipeline/extraction.ts). One unrelated use: the lang declaration on the document's root element, which is docs/design-notes.md's only use of the word and appears once in docs/API.md, under page_main_stripped.

round — one pass of the review loop. The Reader reads the whole document, and the Copy Editor

answers what it raised. max_review_iterations (default 3) caps the editor rounds, so the Reader can read up to four times. The measurement documents mean something else by the word. A benchmark round or a deployed round is one captured run of a corpus through the pipeline, named like runs-postswap-312 and kept with its own logs and prices; the two labels say where it ran. All six documents that use the word that way say so at the top — docs/API.md, docs/cost.md, docs/design-notes.md, docs/models.md, docs/sprint-246.md and docs/verifier-calibration.md. One line of verifier-calibration.md uses it for a third thing, a page's correction pass ("wasted rounds").

Quick start

Requires Node.js 24+ (the service runs TypeScript directly via Node's built-in type stripping and uses the built-in node:sqlite), and a git checkout of the agent library (this repo's agents/ directory works). For PDF uploads, install poppler-utils (pdftoppm/pdfinfo, plus pdftohtml to carry the PDF's links into the output) — brew install poppler on macOS, apt-get install poppler-utils on Debian/Ubuntu. (The Docker image includes it.) pdftoppm renders one page at a time on one core, so Iris divides a PDF's page range between several of them — up to one per core the host reports, and never more than the document has pages: a 25-page document that took 12.5 s in one process takes 3.9 s across four. (Past about a dozen cores a 25-page document stops getting faster, since the shards are already down to two pages each.) It is the uploader who waits for this — the route rasterizes before it answers — so cores are worth giving a deployment that takes PDFs. The budget is shared across concurrent uploads rather than granted to each: a second document arriving mid-render takes what is left, down to the single process it would have had before.

git clone https://github.com/EqualifyEverything/equalify-iris
cd equalify-iris
npm install

cp .env.example .env          # a model provider key; GitHub App settings are optional
cp config.example.yaml config.yaml

# load env and run
set -a; source .env; set +a
npm start                     # -> http://localhost:8080

Or with Docker (multi-arch; Mac Mini / Linux ARM are first-class targets):

cp .env.example .env          # fill in values
docker compose up

Check it's alive:

curl http://localhost:8080/v1/health

Or just open the accessible browser app at the root for a no-API walkthrough (sign in with GitHub → upload page images → convert → view the accessible HTML):

http://localhost:8080/

Configuration

Deployment is configured in config.yaml. ${ENV_VAR} references are expanded from the environment at startup; changes require a restart.

Storage: local filesystem + a single SQLite file by default. agents/ is a git

checkout modified only by git pull from upstream. These are the only backends v1 ships — a Postgres or S3 backend was designed for and is deliberately not built (design notes).

Model providers (docs/models.md): each agent declares a capability

(vision, structured_output, text); the deployment maps capabilities to a provider + concrete model. v1 ships OpenRouter and Amazon Bedrock adapters, and adding one is a small adapter implementing the ModelProvider interface in src/providers/types.ts. Models are set per provider (default_model + per_capability), and can be overridden per agent via providers.per_agent — either a string (provider only) or { provider, model }. Resolution falls back: per-agent model → provider per_capability → provider default_model. The per-agent key has to be an agent Iris actually dispatches — page, reader, copy_editor, feedback, builder, or any specialist file in agents/. There is no table key, because joining a table split across a page break is a copy_editor call. **Getting the key wrong does not stop the run**, it just silently doesn't swap anything, so confirm a swap against by_agent.<agent>.models in diagnostics rather than assuming it. Two other keys per provider: max_tokens (default 32000) is the per-call output ceiling, and a reply that stops at it counts as a failed call rather than a short one; on Bedrock, api chooses the wire dialect — invoke (the default, and what every published number here was measured through) or converse, the only one that can reach a non-Anthropic model. Both adapters stream and enforce three silence timeouts. Why each of those behaves as it does: design notes.

Concurrency: two independent knobs under defaults.

extraction_concurrency is within a run — pages in parallel during extraction, and during review both the Reader's chunk reads and the section calls a too-long correction round is re-made with, all under that one cap, so a run's in-flight calls never exceed it in either phase; max_concurrent_runs is across sessions. Peak in-flight model calls is the product of the two, so the second is the one that bounds what the machine is doing — each run also holds a jsdom+axe instance. Uploads beyond the cap wait, in FIFO order, in status: "queued"; the wait appears in the session's run log as run_queued / run_dequeued (waited_ms). Nothing is rejected — the upload is already received and on disk, so a 429 would discard work the user has already paid for. The cap is global rather than per user because the resources it protects (memory, jsdom, the provider's rate limit) are global.

Request limits: the run cap bounds work the deployment has accepted;

server.rate_limits bounds what can be asked of it, which is a different problem — the cheap endpoints never reach the queue, and every one of them queries SQLite synchronously on the one event loop. Per minute: general_per_minute across /v1 (240, liveness probe exempt), auth_per_minute on /v1/auth (60 — each device-flow poll costs an outbound call to GitHub, so this protects your GitHub rate limit rather than a password), upload_per_minute on session creation (12), plus max_upload_memory_mb (256), which meters the bytes of upload body arriving at once so that concurrent small uploads never wait on each other. These gates refuse (429 with Retry-After and the standard error body) rather than wait, since nothing has been received yet — the opposite of the run cap, for the same reason. A request counts against its GitHub token once validated and against its address otherwise, so one user's polling cannot spend everyone's budget from behind a shared NAT. GET /v1/limits publishes whatever is in effect. Set enabled: false to turn it off where a proxy already does the job.

Behind a reverse proxy: set server.trust_proxy to the number of proxies in front of Iris

(1 for a single Caddy/nginx). Without it every caller presents as the proxy's address and shares one rate-limit bucket — the log warns when it sees an X-Forwarded-For while this is unset. true is coerced to 1 with a warning: trusting the whole chain means trusting the part of the header a client wrote, which would make the per-address limits bound nothing. Express's own vocabulary (loopback, or a list of proxy addresses and subnets) works too; anything it cannot interpret warns and trusts nothing, rather than taking the process down at startup.

GitHub: GitHub is the auth mechanism — a user is their GitHub account, and a token

is required on every call. By default the service uses a bundled GitHub App via the device flow — no per-operator app setup, no secret (the same approach the gh CLI uses). Set github.client_id only to point at your own GitHub App; client_secret is needed only if you enable the web redirect flow. No OAuth scope is requested at all — the app's one permission comes from installing it on upstream_repo — see GitHub is the only SSO layer.

GitHub is the only SSO layer, and tokens are required

There is no anonymous mode, no API key, and no second identity provider. Every request carries a user's GitHub token, and that token is what files the session's feedback back to the shared agent library — as an issue, under that user's own GitHub identity.

That is the sustainability model, not an implementation detail. The agents in agents/ get better because sessions run against real documents and real corrections; a user who could consume the service without contributing would be taking from a library nobody was refilling. Requiring GitHub auth is how using Iris and improving it become the same act, and how each contribution is credited to the person who produced it. If you would rather your users not contribute, this is not the service to deploy.

A user's token is never written to disk. It arrives in the Authorization header, is used in memory for the request and for the run it authorizes, and is gone when the run ends. There is no github_token column in data/iris.sqlite and no token file — a stolen copy of the database is a list of GitHub user IDs and logins, not GitHub access. Revoking at github.com is the whole mechanism; there is nothing here to rotate or purge.

Everything an operator needs beyond that is in docs/github-auth.md: registering your own GitHub App, what a private upstream_repo can and cannot accept, github.issue_token and what it trades away, the 5-minute identity cache, and — if you are coming from an earlier build — the two config changes that can stop a working deployment, plus why a data/iris.sqlite from back then has to be deleted rather than adopted.

API

All endpoints are under /v1 and (except auth, health, stats and limits) require Authorization: Bearer <github_token>. /v1/quality is the one exception in the other direction: it takes a bearer token too, but its own shared secret rather than a GitHub one.

Method & path	Purpose
`GET /v1/health`	Liveness probe
`GET /v1/stats`	Public tally of pages converted, plus a two-number quality summary (no token; aggregate only)
`GET /v1/quality`	Deployment-wide tally of output quality (own shared secret, off by default; aggregate only)
`GET /v1/limits`	What an upload may be — formats, per-image size, page cap (no token)
`GET /v1/auth/github/start`	Begin OAuth (web clients)
`GET /v1/auth/github/callback`	OAuth callback → returns access token
`POST /v1/auth/github/device`	Begin device flow (CLI clients)
`POST /v1/auth/github/device/poll`	Poll device flow (send `{ "device_code": ... }`)
`GET /v1/me`	Current GitHub user + config
`GET /v1/sessions`	List the caller's sessions
`POST /v1/sessions`	Create a session, upload images and/or PDFs (`multipart/form-data`)
`GET /v1/sessions/{id}`	Poll status
`GET /v1/sessions/{id}/output`	Fetch the HTML when ready
`POST /v1/sessions/{id}/feedback`	Submit feedback, trigger a re-run
`POST /v1/sessions/{id}/close`	Finalize the session and clean tmp
`GET /v1/sessions/{id}/logs`	Fetch the run log (ndjson)
`GET /v1/sessions/{id}/diagnostics`	Cost/timing/health summary (token counts per run and per agent, phase + per-call durations, in-flight/hung call)

Full copy-pasteable bash/curl walkthrough of every endpoint: docs/API.md. To prove the endpoints work end-to-end (mock GitHub + mock model, no credentials needed): ./test/e2e.sh.

Which model to run each agent on and what each one costs: docs/models.md. No model is named in Iris's code, so the price is a config choice: **nothing per token against a self-hosted open-weight model, or about 10.7 cents a page for the suggested setup.** That 10.7 is measured over 100 pages end to end, on a round that ran the page model this one replaced — so the suggested setup is a little cheaper than the figure and has not been re-priced. Broken down by step: docs/cost.md. How it got there — **19.4 cents when the model-selection sprint started, 10.7 measured after two lines of config and no code change** — with the recommended approach for every step and the evidence under each one: docs/sprint-246.md.

Example — create a session (order of images parts is the processing order):

curl -X POST http://localhost:8080/v1/sessions \
  -H "Authorization: Bearer $TOKEN" \
  -F "images=@page-001.png" \
  -F "images=@page-002.png"

Then poll GET /v1/sessions/{id} until status is ready_for_review, fetch GET /v1/sessions/{id}/output, and POST /v1/sessions/{id}/close to finalize.

Layout

agents/                  # the agent library: page.md (the general pass), feedback.md,
                         #   and specialists dispatched by name
src/
  config.ts              # config loader (${ENV} expansion)
  providers/             # ModelProvider interface + openrouter & bedrock adapters
  agents/loader.ts       # loads agent .md files, pins git SHA
  pipeline/
    orchestrator.ts      # runs the phases, persists results, drives learning
    extraction.ts        # per-page vision pass (+ verify, correct, specialist merge)
    assembly.ts          # joins fragments into the document shell
    review.ts            # reader -> copy editor -> re-lint loop (scoped image payload)
    pageindex.ts         # page-number index shared by the reader + feedback scoping
    lint.ts              # axe-core in jsdom (color-contrast disabled)
    flatten.ts           # screen-reader text view, used by reader + coverage
    feedback.ts          # verify / scope / classify / train + regression gate
    memory.ts            # per-agent example bank of learned corrections
    regression.ts        # fixture capture + pruning on close
    contribute.ts        # drafts suggested agents, files issues
    calibration.ts       # does the fidelity verifier discriminate? (docs/verifier-calibration.md)
  tools/calibrate.ts     # CLI for that measurement; nothing in a run imports it
  util/queue.ts          # bounded FIFO run queue (cross-session concurrency cap)
  auth/                  # GitHub OAuth + device flow + bearer middleware
  github/                # auto-files labeled agent-suggestion issues
  store/                 # node:sqlite metadata store + on-disk session layout
  routes/                # /v1 endpoints
  index.ts               # server entry point
data/                    # sessions/, tmp/, and the SQLite DB (created at runtime)

Document	What is in it
docs/API.md	Every endpoint, with copy-pasteable `curl`. The run log's fields.
docs/design-notes.md	Why the code is the way it is. Read this before changing it.
docs/models.md	Which model runs which agent, and what each choice is worth.
docs/github-auth.md	Deploying the GitHub sign-in: your own app, a private upstream, an older database.
docs/cost.md	What a page costs, measured.
docs/ci.md	The five workflows that run this repo, including the bot that will review your PR.
docs/verifier-calibration.md	How to re-measure whether the page verifier catches damage.
docs/sprint-246.md	The cost sprint's findings, including what it got wrong.
CONTRIBUTING.md	How to open a PR here, and what the agent library is.

Contributing

See CONTRIBUTING.md and our Code of Conduct. Found an accessibility barrier — in the app or in the HTML it produces? Please open an Accessibility issue; those are our top priority.

PRs get an automated review before a human reads them — see Automated code review for what it looks at and, more usefully, what it deliberately does not flag (style, formatting, naming, "you could also do X", pre-existing issues your PR doesn't touch). One exception: it does check docs prose against CONTRIBUTING.md's plain-language requirement, always as a non-blocking note. Editing this file is in scope.

License

GNU AGPL-3.0-or-later. Iris is copyleft: if you modify it and run it as a network service, you must make your modified source available to its users (AGPL §13).

Iris is maintained by Equalify Inc., the University of Illinois Chicago, and California State University.

Commercial hosting and support are offered by Equalify Inc. The hosted and self-hosted versions are functionally identical — what you are paying for is operational (managed deployment, monitoring, accessibility consulting), not features withheld from this repo. Please consider hiring them to host or support your instance.

📦 EqualifyEverything / equalify-iris