The notes existed but there was nowhere to write them: a CLI command on a
laptop, a tool call through Claude, or a file in a Docker volume. None of
those is reachable from a phone in a lesson, which is where notes are
actually taken.
So: `/app`, served only when WEB_PASSWORD is set. A login, the day's
notes, and a settings page for the Schulcloud token — the one surface
here meant for a person rather than a program.
The shape follows how the notes are written: one note per school day,
one `##` heading per lesson, prose and lists and tables beneath. That
turns out to be the design decision that matters, twice over.
First, it is what lets WebUntis earn its keep. Opening a day with no
note fills in that day's lessons — numbered, with times, teacher and
room, cancellations dropped and substitutions marked. Retyping the
timetable is exactly the work the second upstream exists to avoid, and
"Stunden ergänzen" tops up a note started before the day ended without
touching what is already written.
Second, it changes how notes are indexed. A day note is indexed per
lesson, not whole: search answers "my own note, Deutsch, 18.09.2026"
rather than "my own note, Friday", and `list_notes subject=Deutsch`
finds a day whose frontmatter names no subject at all. Indexed whole,
every hit would read as a weekday and "what did we do in Deutsch" would
match notes whose other five lessons were something else. `lessonHeading`
and `subjectFromHeading` are a loop — the app writes the heading, the
indexer reads the subject back out — and a test holds them to it.
Notes taken in a lesson cannot be retaken, so the editor is built
around not losing them: autosave, every keystroke mirrored to local
storage, a save when the phone locks, and a fallback to the local copy
when the request never arrives. A save that would overwrite a version
the editor never saw is refused and the choice handed back — the notes
folder is synced and open in more than one place, and a phone must not
silently win over a laptop. `replaceNote` is separate from `writeNote`
for that reason: never-overwrite is right for `add_note` and exactly
wrong for an editor.
WEB_PASSWORD is the first credential here a human types, so it is the
first that can be guessed: scrypt at startup, never stored or compared
in the clear, per-address rate limiting — which is not decoration, since
the scrypt cost is itself a denial-of-service vector without it. The
session is a signed HttpOnly SameSite=Strict cookie whose key is derived
from the password, so changing it logs everyone out and there is no
second secret to keep. It opens /api, because a session is the user, and
never /mcp, because nothing in a browser speaks MCP.
Also here, because the app made them matter: frontmatter now reads the
indented `- item` list form editors write, so an Obsidian vault
round-trips its tags; and a four-digit folder is a filing scheme, not a
subject, so `2026/` does not file a school year under one.
357 tests; 106/107 smoke against the local instance, the one failure
being the H5P service that instance does not run.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Schulcloud says what was uploaded and WebUntis says what was scheduled.
Neither says what was *taught* — which point the teacher laboured, which
example landed, what "will definitely come up". That lives in two places
this server could not reach: the notes the user takes in the lesson, and
WebUntis' class register.
Notes are a directory of Markdown files (NOTES_DIR), not a table. They
have to be writable from a phone in a classroom, readable when Postgres
is down, and outlive this project, and files are the only shape that is
all three — so the files are the truth and the index is a view of them,
the same split as file_texts and the mirror. list_notes and get_note read
disk, so they answer before the first crawl; search, what_changed and all
three German prompts read them alongside the Schulcloud material.
add_note writes one, and is the only thing in this server that writes
anything. That is not a hole in the read-only invariant but a different
store: it is bounded to NOTES_DIR by the same safeComponent/resolveWithin
pair that stops a hostile Schulcloud filename escaping the mirror, so a
note titled ../../.ssh/authorized_keys becomes a filename. Schulcloud and
WebUntis stay GET-only and allowlisted respectively. NOTES_READONLY
refuses writes outright.
Appending targets the *lesson*, not the title: "halt das auch noch fest"
mid-lesson carries a new title, and deriving the path from it would start
a second note every time, which is the one thing append exists to prevent.
Notes.app has no export — its bodies are compressed protobuf and the
iCloud copy is encrypted — so scripting the app is not the clumsy route
to the notes but the only one. scripts/export-apple-notes.js reads them
through AppleScript into one JSON object per line, and `schulcloud note
import` converts the HTML to Markdown, takes the Notes folder as the
subject and the *creation* date as the lesson's date. Attachments cannot
come across; a note that was a photo of the board imports as a line
saying so, because importing it empty would hide the loss.
The class register needed one API property to become cheap:
getLessonTopic2017 answers per *series*, not per period, so a term is
reconstructed by asking about the latest period of each lesson series and
merging back by id — a few dozen calls for a school year rather than one
per lesson. untis_lesson_topics now takes a subject as well as a period
id, and UNTIS_HISTORY_DAYS of register goes into the index under a kind
of its own, so "what did we actually do before the test" is searchable.
Sharing the snapshot rather than duplicating it caught one thing on the
way: the search tool's live path had to learn notes too, or fresh=true
would have quietly disagreed with the index.
305 tests; 88/89 smoke against the local instance, the one failure being
the H5P service that instance does not run. The live smoke could not be
retaken: that session has lapsed and needs a fresh jwt cookie.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Schulcloud holds the material for a lesson but not the lesson: this school's
course `times` are empty and it publishes the schedule in WebUntis. So "what
do I have today, and has anything been cancelled" was unanswerable, and the
timetable cannot be typed into a prompt either — it changes daily.
core/untis.ts talks to the API the Untis Mobile app uses, and three tools sit
on it: untis_timetable (a day or a range, Entfall, Vertretung, room changes,
the notes on each period, inline homework, the period id), untis_homework (the
class register's list, which is not Schulcloud's tasks) and
untis_lesson_topics (what earlier lessons of a series actually covered, which
is what says where a subject got to).
Read-only, but not by the Schulcloud client's rule: this API is JSON-RPC, so
every call is a POST, reads included. READ_METHODS is the guarantee instead,
enforced at the single choke point and asserted by a test. It matters because
the key can do what the app can — the live account holds W_OWN_ABSENCE, so
the same key could report the user absent.
What the live instance taught us, all recorded in docs/API.md:
- `startDateTime` ends in Z and is local time. The 08:00 lesson reports
08:00Z, so new Date() would move every lesson by an hour or two.
- A substitution is two periods, the original CANCELLED and the replacement
IRREGULAR beside it, not one period with a changed teacher.
- Announced tests live in the period's info text. The exam module is unused
here, so getExams2017 is always empty and that field carries the tests.
- A day with no lessons is not a holiday: the weeks this account spends in the
company simply have no periods.
- `?v=i3.2` is required, or the call fails with a Java NPE reported as -8998.
Errors arrive with HTTP 200 and an error member. -8504 is a rejected key and
-8524 a drifting clock; the tools name both, because no retry fixes either.
Configuration is all four UNTIS_* values or none — three are identifiers and
the fourth is a credential, so a half-filled block is a paste that went wrong.
Without them the tools are not registered at all, since a tool that can only
fail is worse than a missing one. whoami reports the WebUntis identity and
survives a dead Schulcloud session, so "is the server reachable" no longer
gets a misleadingly total no. mcp-env.sh switches WebUntis off for a fixture
run: that key belongs to the real school.
224 tests. All 10 WebUntis smoke checks pass, with a key and without one; the
Schulcloud checks in those runs answer 401 because this machine's session is
logged out.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
claude.ai's connector dialog does offer request headers, on its second step,
after the URL has been probed, so the connector no longer needs the secret
path. MCP_AUTH_TOKEN already worked there as a bearer or X-Api-Key, but it
also opens /api, which can replace the Schulcloud token and stream the file
mirror, and claude.ai stores the header's value.
MCP_CONNECTOR_TOKEN is a second token, accepted on /mcp only and refused on
/api, and rotated without touching Claude Code or the CLI. The config refuses
one shorter than 32 characters, equal to MCP_AUTH_TOKEN, or set without it,
and never echoes a value. Every accepted token is compared in full, so the
timing does not tell which one matched.
The gate also takes a bare Authorization value, because claude.ai sends a
header exactly as typed and its docs warn that most servers reject a token
entered without "Bearer ". It takes X-Auth-Token too, the other name its
dialog offers.
The docs now set up the header; the secret path stays as a fallback for
clients that cannot send one. 184 tests. Smoke 79/79 and 77/77 on the local
instance.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
claude.ai's connector dialog takes a name and a URL. Sending a bearer token
needs a "Request headers" beta most accounts lack, and OAuth is not built
yet, so with MCP_PATH_SECRET set the endpoint is also served at
/<secret>/mcp without the bearer token — a trial until OAuth replaces it.
The path is the credential there. It is compared in constant time, and a
wrong one answers 404 like any unknown path. The config refuses fewer than 32
URL-safe characters and never echoes the value, nothing in the server logs
request paths, and the Caddy snippet rewrites the segment before an access
log entry is written (verified against Caddy 2.11). Claude Code and the CLI
keep the bearer token; DEPLOYMENT.md says what the path trades away.
178 tests. Smoke 76/76 and 74/74 on the local instance.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
A token lasts 30 days and only a browser login yields one — the account is
federated, so the server cannot mint it. Replacing it meant editing .env and
recreating the container, every month.
`schulcloud token set` (a hidden prompt, or piped input) and a /token page
both send it to PUT /api/token. The server checks it with Schulcloud first —
well-formed, unexpired, still logged in, the same account — then swaps it
into the config every request reads, restarts the keepalive and saves it in
STATE_DIR, a new volume, with mode 0600. At startup the newer of the saved
token and TSC_JWT_COOKIE wins, unless they belong to different accounts. A
refused paste changes nothing, and the token is never logged.
The keepalive's pings carry a generation, so a 401 for the old token that
arrives after a swap cannot stop the new cycle. `schulcloud token`, whoami
and the log report the expiry and warn a week ahead.
Found on the way: a host that is off for more than two hours loses the
session however long the token has left — this machine lost it overnight —
which is what the always-on Pi is for.
174 tests. Smoke 72/72 on the local instance, and a real swap verified end to
end there.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Many teachers never use topics or boards; their material sits in the
course's file area, and the tools answered "0 files" for courses holding
dozens of worksheets — 21 of 26 courses on the live account. Persönliche,
Kurs-, Team- and Geteilte Dateien live in the legacy file store, not in
files-storage, and its service is not in the public ingress. The only way in
is the legacy client: HTML listings, and GET /files/signedurl for a
pre-signed download.
core/legacy-files.ts turns that into one path tree — /my, /courses/<course>,
/teams/<team>, /shared — resolving names that contain "/", ids anywhere in a
path, and wrong or ambiguous names with a message saying what is there. A
listing that does not parse throws; it never reads as an empty folder.
Some of the legacy client's GET routes write (GET /files/share/ mints a
share token), so getFileManagerPage allows only the listing routes, by
pattern. Signed URLs are fetched with no credentials and must be https.
- MCP: fs_list, fs_tree, fs_find and fs_read; get_course lists course files.
- CLI: schulcloud fs ls, tree, find and get, recursive and resumable.
- API: /api/fs/list, tree, find and file.
- Index: the crawl walks the file manager (INDEX_FILE_MANAGER, on by
default), so search covers the text inside those files and sync mirrors
them under <course>/Kurs-Dateien.
The local instance gains a fixture for all four areas. It needed a loopback,
so signed URLs open from the host, and a pre-created bucket, since MinIO
does not implement PutBucketCors.
135 tests. Smoke 55/55 live; 57/57 and 55/55 on the local instance.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Every area — courses, rooms, boards, topics, tasks, files, quizzes, teams,
groups, submissions, grades — was checked for data the instance has and the
tools did not show.
Grades and feedback. A teacher's /homework page is a different page from a
student's: grade and comment live in the grading form, one block per
submission, so a teacher account reported every graded submission as having
neither. parseTeacherGrading reads the form, and list_submissions can now
include the written feedback and who handed the work in.
Names. /api/v1 is partly served: courses, users and classes survive in the
deployment's ingress table, and users/{id} is the only route from an id to a
name. Submitters, file creators and course teachers resolve through it, and
degrade to "not visible to this account" where a student may not read them.
Courses, rooms and classes. get_course adds the description, teachers,
member count and weekly timetable from /api/v1/courses. list_classes is new.
get_room reports what the account may do — allowedOperations is an object of
booleans, not the list it was typed as — and applicants and invitation links
where it may manage them.
Board and topic content. Link descriptions, image alt text, drawing and
video-conference titles, the ids behind external tools and H5P content (the
only thing resembling a quiz), and what a deleted element used to be. Topic
Etherpad pads are read like board pads, and htmlToText keeps table columns
apart and drops template indentation.
Files. A scan with no text layer falls back to the preview endpoint, whose
width and outputFormat are undocumented enums, so Claude gets a picture of
the page; list_files reports counts and sizes. Teams stay documented as
unreadable at any API version; their files come later.
What the crawl missed. Tasks attached to topics (18 of 60 on the live
account), each course's own file area, and — behind INDEX_PERSONAL_FILES —
personal files and submissions with their grade comments, so search and
what_changed cover grading. A submission hit points at get_task.
The local instance's preview profile gets an ImageMagick policy that allows
the coders its 7.1.2 build needs; the image's own denies them all.
110 tests.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Node 22.16 runs TypeScript only behind --experimental-strip-types (on by
default from 22.18), so `npm test` failed on every file with
ERR_UNKNOWN_FILE_EXTENSION. The flag is harmless on newer versions.
probe and session-diagnose still imported dist/schulcloud/client.js, which
the move to core/ renamed, so both scripts died at import.
A relative MIRROR_DIR broke file serving: res.sendFile refuses a relative
path, and resolveWithin returns an absolute path only when its root is one.
The config resolves it once, at load.
package-lock.json is what `npm install` records today: the `schulcloud`
bin, and no stale peer flags. 101 tests.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Store: crawl generations as the sync cursor. Diffs compare generations
on entity identity plus a content digest, never on upstream timestamps —
GET /course-rooms/{id}/board returns request time as updatedAt for most
elements, so a timestamp cursor would report every board as changed on
every crawl. Identity diffing also yields deletions, which no timestamp
scheme can. A per-course crawl carries the other courses' rows forward
so every completed generation is a complete picture and any two diff
directly; without that a partial crawl reads as a mass deletion.
FTS uses the german dictionary with weighted title/body, plus a pg_trgm
arm because stemming will not match "Datenschutz" inside
"Datenschutzgrundverordnung" and German compounds make that the common
case. file_texts is keyed by file record id and deliberately outlives
generations: records are immutable upstream, so text extracted once is
valid forever and a re-crawl of unchanged content costs nothing.
Store.open returns undefined instead of throwing when Postgres is
unreachable — the index is an accelerator, and a Pi that loses its
database should get slower, not broken.
core/paths.ts is the security boundary for the mirror. Course titles,
card titles and filenames are all user-supplied upstream, so this is
where a hostile name stops being text and becomes a path. Two bugs found
by its own tests: "///" produced "---" instead of falling back, and dot
runs survived mid-component. Now no ".." can survive anywhere, which
makes the invariant checkable rather than a claim about ordering.
Indexer coalesces concurrent refreshes onto one run and enforces a
minimum interval, since a full crawl is ~270 requests from an account
that looks like a student.
9 store tests against a real Postgres (mocks would test nothing here)
and 13 path tests; 47 total.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
The JWT's exp claim says 30 days, and I took that as the session
lifetime. It is only an outer ceiling. The server also keeps a per-token
whitelist entry in Valkey (jwt:{accountId}:{jti}) whose TTL is
JWT_TIMEOUT_SECONDS — 7200s on this instance — and JwtStrategy.validate
re-sets it on every authenticated request. Two hours idle and the token
is rejected with 29 days still on exp.
Proven, not inferred: the token from yesterday returned 401 at 13.8h old.
The live instance publishes the values unauthenticated at
GET /api/v3/config/public — JWT_TIMEOUT_SECONDS 7200,
JWT_SHOW_TIMEOUT_WARNING_SECONDS 3600, the latter being exactly the
one-hour UI prompt that prompted this investigation.
refresh-session turns out not to be special: it extends through the same
guard as any other route, and uniquely only in returning the remaining
TTL. So the keepalive uses GET /api/v3/me instead, and the server stays
GET-only; the one POST in the repo is in scripts/probe.mjs, where it
reports the idle budget.
JWT_EXTENDED_TIMEOUT_SECONDS (~1 month) exists in the config schema but
is vestigial: privateDevice has no references in the current NestJS
source, and generateJwtAndAddToWhitelist never overrides the TTL.
Also fixes a real breakage this surfaced: TypeScript parameter
properties are rejected by Node's type stripping, so `npm run dev` and
`npm test` both failed on any file reaching them. Rewritten as explicit
fields, and noted in CLAUDE.md.
Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Read-only MCP server exposing a Schulcloud account to Claude: courses,
column boards, lessons, tasks, and file downloads with text extraction.
The API surface was verified against the live instance rather than
inferred from upstream source, which changed several design decisions:
- The `jwt` cookie works verbatim as `Authorization: Bearer` and lasts 30
days, so there is no cookie jar and no refresh-session timer.
- Course contents live at /api/v3/course-rooms/{courseId}/board; there is
no GET /api/v3/courses/{id}.
- Files are a separate service (/api/v3/file/*) with its own OpenAPI doc.
- Board file elements carry no file id; attachments are resolved by
listing files-storage with parentType=boardnodes and the element id.
Read-only by construction: every client method is a GET, including the
api_get escape hatch. The endpoint is internet-facing by necessity, so a
leaked token being unable to act as the user is the key safety property.
Deploys as a container behind the Pi's existing Caddy, guarded by a
constant-time bearer check. Stateless — no database.
Verified: 28 unit tests, plus a 30-check end-to-end run driving a real
MCP client over Streamable HTTP against the live account.
Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
