Input and early have no outgoing interface, output no incoming one, so
the dialog hides those fields (they could only be refused) and a zone
left in a hidden field isn't sent.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
New token on a user's row under Users, with the Account page's dialog
(now tokenDialog in users.js), offering only roles within that user's
permissions.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The ruleset's diff names the chain each hunk is in on its @@ line, as
git names the function. A history entry shows what it did to the
ruleset (web page, hc history diff, GET /history/{id}/diff), rebuilt
from the current configuration by stepping back through the later
entries. A changed setting is listed by its own fields
(builtins.drop_invalid) instead of the whole object.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
One address that used up its allowance filled the bar (100%). The bar
is now all the addresses together, and the dashboard and the rule's
quota line say how many used theirs up.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A program bans an address (every port, or a protocol's ports) for a
time; the ban list says what it is kept from: the firewall, some hosts
behind it, or everything. Bans drop ahead of every rule, close the
address's connections, group IPv6 by /64, are kept in the database
across restarts and audited. Never banned: the inside, the firewall's
own addresses, the caller, the list's never. bans grant (bans:write:LIST),
hc banlist/bans/ban/unban, Traffic -> Bans, a fail2ban action in contrib/,
and failed logins and refused tokens logged for Guard and fail2ban.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.1's thirteenth release candidate. Since rc.12: quota usage
is saved after every change. make test and make e2e (304 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The server hooks the engine's OnChange to save what the quotas used, so
a reboot soon after a change that counts a quota differently doesn't
bring back its usage counted the old way (it was saved every five
minutes and on stop only).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.1's twelfth release candidate. Since rc.11: quota usage
as a percentage; Statistics' quotas link to their rules and include
per-address quotas. make test and make e2e (304 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
What a quota used shows its percentage of the allowance on the Rules
page (line and dialog), the dashboard and in hc quotas. Statistics'
Quotas card links each entry to its rule, named, without the share of
the total; per-address quotas are in it at last: their quota:rN series
is the sum of their addresses.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.1's eleventh release candidate. Since rc.10: a quota keeps
what it used when its rule counts it differently (per address to a total:
the sum; wider groups: added up), or starts again with a warning. make
test, the real-nft quota test and make e2e (304 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
model.QuotaCarry says what becomes of a quota's use when its rule
changes how it counts; the firewall's apply follows it, comparing with
the rules in force: per address to a total starts at the addresses' sum,
wider groups add up their addresses, and what can't be carried (a total
to per address, per source to per destination, finer groups) starts
again, with the engine warning quota_restarts on that change. Before,
per source to per destination kept the sources' use as destinations',
and regrouping left old entries behind.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.1's tenth release candidate. Since rc.9: rules read as a
direction ("lan → wan", "any but wan → any"). make test and make e2e
(297 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A match's zones are written "lan → wan" (or "any but wan → any", and
"lan → firewall" / "firewall → wan" in the input and output chains)
instead of "in lan · out wan" and "in not wan"; exclusions read "from
any but X". The Rules and NAT pages and hc; flags and JSON unchanged.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.1's ninth release candidate. Since rc.8: a rule's quota is
one line on the Rules page, with its usage, resets and actions in a
dialog. make test passes; the web UI was checked in a browser.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A rule's quota shows on its row as one line (what it used, how it
resets) that opens a dialog with the rest: the allowance, last and next
reset, usage (each address's, with Reset and Give back), and Reset and
Give back for everyone.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.1's eighth release candidate. Since rc.7: a quota can be
reset for one address, or topped up until its next reset (hc rule
reset-quota --address/--give, Give back in the web UI). make test, the
real-nft quota test and make e2e (297 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
POST /rules/{ref}/reset-quota takes an optional address (one entry of a
per-address quota starts again) and give (bytes taken off what was used,
one address's or everyone's, until the next reset). The firewall keeps
the adjustment for its next apply, which writes the new usage into the
ruleset; housecarld applies at once and saves the usage. hc rule
reset-quota --address/--give; Reset and Give back in the web UI, per
address in the usage dialog.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.1's seventh release candidate. Since rc.6: names beside
inside addresses, by reverse lookups (names in housecarl.yaml, POST
/names, hc --no-names); hc stats top devices lists each device once.
make test and make e2e (289 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Reverse lookups (internal/names, POST /names) put a name beside each
inside address in connections, the log, quota usage, the dashboard's
quotas and the statistics' devices and blocked sources, in the web UI
and hc (--no-names to leave them out). Only inside addresses are looked
up: an inside zone's networks, and private ones outside the external
zones'. Names are cached (names.cache, 10m) and never stored;
names.resolver picks the DNS server.
Also: hc stats top devices listed each device twice; the dashboard's
quotas named the rule's ID twice.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.1's sixth release candidate. Since rc.5: the dashboard
lists the rules' quotas. make test passes.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A Quotas panel with each quota's allowance, use (or, per address, the
count and the busiest), a usage bar and the next reset. The usage bar
moves to widgets.js and the Rules page's usage dialog shares it.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.1's fifth release candidate. Since rc.4: a rule added
before, after or first is placed in the same change it is created in
(one history entry, kept in a changeset). make test and make e2e (286
checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
hc rule add --before/--after/--first created the rule at the end of its
chain and then moved it: two history entries, two probations, the rule
briefly in force in the wrong place, and in a changeset the place was
lost. POST /rules (and the other ordered kinds) now takes ?before=ID,
?after=ID or ?first=1, kept with the operation when staged.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.1's fourth release candidate. Since rc.3: the matrix reads
raw rules that are a match and a verdict (the imported neighbour
discovery rule is no longer unknown), and links to a rule open it on the
Rules page, highlighted, with rule IDs shown. make test and make e2e
(286 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A rule named in the matrix, the log, the tracer, statistics or the
dashboard opens the Rules page on its chain, scrolled to it and
highlighted (#/rules?rule=ID; the chain is looked up when the link has
none). The Rules page shows each rule's ID beside its order.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A raw rule that matches and then accepts, drops or rejects (counter and
log allowed, no interfaces) is an exception of every pair of its chain,
shown as "raw: …", instead of unknown; one not for new connections is
skipped like any rule. Interfaces, jumps, NAT, set and verdict maps
stay unknown. The imported IPv6 neighbour discovery rule (hop limit
255) now reads as allowed.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.1's third release candidate. Since rc.2: a clearer zone
matrix (allow, block or partly, what is let through, hits per rule, hc
matrix aligned in colour), and counters that forget objects no longer
there (after an import with --replace). make test and make e2e (285
checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A cell reads allow, block or partly (some new connections let through,
the rest not), with its exceptions counted by what they do (+3 -1), and
what they let through: services with the addresses they are limited to,
under the grid in hc matrix and in each cell on the Matrix page. A zone
to itself is marked: only traffic routed between its interfaces passes
the firewall. The details list each rule's hits. hc matrix pads the
grid by visible width: the colours' escape codes had thrown it out of
line.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
hc counters kept listing the objects of a configuration replaced since
housecarld started (an import with --replace gives every object a new
ID) beside the current ones. Disabled objects, built-ins and policies
keep their totals.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.1's second release candidate. Since rc.1: shadow mode,
Housecarl's ruleset loaded beside the firewall in force, counting,
logging and tracing what it would drop while changing nothing
(docs/shadow.md). make test (with nft 1.1.3), make e2e (282 checks) and
the systemd package test pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
shadow.enabled in housecarl.yaml loads Housecarl's ruleset so that it
blocks, rejects and translates nothing: drops and rejects count and
accept (an accept only ends Housecarl's chain), policies accept and log
what they would drop, NAT only counts, MSS clamping and the flowtable
are left out, and raw rules that do more than accept, drop or reject are
left out with a warning. Comments mark what would happen ([would drop]).
Filter chains run after the other firewall's (+10) or before (-10); NAT
chains always first. Every change is checked by nftables in both forms.
No probation; takeovers and closing connections are refused. The boot
fallback filters nothing. internal/tablewatch puts the table back after
a flush ruleset. Mode in status, healthz, whoami, the web UI, the log
and the tracer; hc ruleset --enforcing. docs/shadow.md.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.1's first release candidate. Since 0.1.0: an importer
that keeps what rulesets mean in the cases an audit found (chains on one
hook, jumps, repeated matches, forward accepts, raw rules' sets), zone
names given at import, timeout sets as dynamic sets, and multi-port
DNATs. make test (with nft 1.1.3) and make e2e (246 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Fixes from an audit of the importer, each of which could change what an
imported ruleset does: two base chains on one hook imported their rules
twice (and hoisted the second's built-ins), now in priority order with
the stricter policy; raw rules from a jumped-to chain lost the jump's
condition, now put in front; a jump and a rule matching one field are
combined only when one's addresses lie within the other's; a second
match on a field replaced the first, and != on hop limit and TCP flags
read as ==, now kept raw; a forward accept without ct status dnat no
longer folds into the port forward, nor an interface-limited IPv6
accept into an open pinhole; raw rules' set references are renamed
(NAME_v4/_v6) or written out, so nftables takes them; DNATs with
matches a forward can't hold are left out with a note.
Sets with flags timeout become dynamic sets; a DNAT of several ports one
forward per port. Zone names: --zone IFACE=NAME (and on the Import
page), VLAN defines, more suffixes, and a note on where each name came
from. testdata/audit.nft covers the cases, checked with nft 1.1.3.
make test and make e2e (246 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.0. Since rc.7: the boot ruleset fails closed (a fallback
keeps anything new from the internet out if it doesn't load), the
flowtable follows devices that appear later or reconnect, /healthz for
monitoring, renaming zones, sets and services with their references,
and an import that keeps a chain's head in order. make test (with nft
1.1.3) and make e2e (242 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The boot unit fails closed: if ruleset.nft doesn't load, it loads
ruleset-fallback.nft (render.Fallback), saved beside it from the same
configuration: nothing new in from external zones, established, the
ICMPv6 IPv6 needs and DHCPv6 replies let in, the inside left alone and
masqueraded, and the unit marked failed with a critical message.
housecarld replaces it when it applies; status, the dashboard and
/healthz say while it is in force. no_external_zone now also says the
fallback closes everything without an external zone.
The boot ruleset has no flowtable: nftables on Debian 13's kernel
refuses one naming a device that doesn't exist yet (ppp0 before PPPoE),
and with it the whole file. internal/linkwatch listens to rtnetlink link
messages; housecarld applies again when a flowtable device appears or
comes back as a new interface (by ifindex), under the engine's lock.
docs/flowtable.md: what it does, when to use it and when not, how.
GET /healthz reports firewall (applied, unconfigured, fallback,
missing), changes on probation and the machine's warnings, with 503
unless in force, read at most every five seconds.
Renaming a zone, set or service changes what names it in the same
change (one history entry, one undo); dynamic sets keep their names.
The importer keeps a chain's head in order: once a would-be built-in
stays a rule, the ones after it do too, so the maintainer's ICMPv6
accepts stay behind the invalid drop as written. hc settings set
--flowtable none empties the list.
make test (nft 1.1.3) and make e2e (242 checks, with VLAN
sub-interfaces, the fallback and the flowtable) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.0's seventh release candidate. Since rc.6: statistics
over time (traffic per zone and device, drops, blocked sources, hits,
connections, quotas, the machine). make test (with nft 1.1.3) and make
e2e (188 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
internal/stats samples every minute what the kernel already counts: the
interfaces' counters (per zone too), Housecarl's table (hits per rule,
built-in and policy; drops by chain; quotas; per-device sets), the
connection tracking table, and housecarld's and the host's memory, CPU
and load. Logged drops feed top lists of sources and what they tried.
Aggregates go to a database of their own (stats.db; per minute 7 days,
per hour 90 days, per day 2 years), with the store and queries from
Jarl's.
Traffic per inside device is a setting (stats_per_device): counting sets
stats_up/down_v4/v6 and rules at the top of the forward chain, IPv6 per
/64, carried across reloads. Set names starting with meter_, conn_,
quota_ or stats_ are reserved (set_name_reserved).
GET /stats/{status,summary,timeline,top,hits,heatmap}, hc stats, a
Statistics page with Jarl's charts, two charts on the dashboard, and a
conntrack_full warning. e2e: 188 checks.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.0's sixth release candidate. Since rc.5: the zone
matrix, what the rules do to new connections between zones. make test
(with nft 1.1.3) and make e2e (166 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
internal/matrix walks each pair's rules in order, as nftables would, for
new connections: zone → zone (forward), zone → the firewall (input) and
back (output), with the built-ins that act on new connections. A rule
for the whole pair decides it; one for part of its traffic (addresses,
services, times, rates, a quota) is an exception; the rest falls to the
policy. Rules whose addresses all lie in networks connected to other
zones are left out of a pair. GET /matrix (with ?changeset, pending
changes), hc matrix [FROM TO], and a Matrix page whose cells open their
rules.
e2e: 166 checks, among them the matrix of the maintainer's imported
ruleset.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.0's fifth release candidate. Since rc.4: the connections
the firewall tracks, and closing them; rules that check every packet,
so a block stops connections already open; and a packet tracer that
follows packets through every table's rules. make test (with nft
1.1.3), make e2e (157 checks) and the package test pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
- Connections: the kernel's tracked connections, read and closed over
ctnetlink (internal/conntrack, raw netlink like the drop log), with
their NAT and TCP state; closing one makes the rules check its next
packet again (GET /connections, POST /connections/close; hc
connections; Traffic → Connections).
- Rules can check every packet (every_packet, --every-packet): before
established connections are accepted, so a drop or reject also stops
connections already open. They can't accept.
- A packet tracer (internal/trace): a table of its own, inet
housecarl-trace, marks the packets a filter picks, `nft monitor trace`
reports every rule and policy they meet in every table, and the tracer
names what accepted or dropped them, Housecarl's rules by name (POST,
GET, DELETE /trace; hc trace; Traffic → Trace). One trace at a time,
at most 200 packets and 20 a second; the table goes when it ends.
e2e: 157 checks, among them an upload a normal block doesn't stop and an
every-packet one does, and a trace naming the blocking rule.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.0's fourth release candidate. Since rc.3: undo is staged
like any edit, each chain's built-ins have a window of their own, the
dashboard warns while nftables.service is enabled or an imported table
still applies, and raw rules and dynamic sets refuse fields they used to
ignore silently. make test (with nft 1.1.3), make e2e (140 checks) and
the package test pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
- Undo is staged like any edit: in review mode the web UI's Undo, and hc
history undo with -C or HOUSECARL_CHANGESET, add a revert operation
that checks, when replayed, that nothing it touches changed since;
applied, History links the entries. Imports and takeovers still can't
be staged.
- The rules page sums up a chain's built-ins in one line; a window lists
them with what they do and their hits, and switches them.
- Warnings about the machine (dashboard, hc status): nftables.service
enabled (it loads /etc/nftables.conf at boot and flushes every table
when stopped), and the imported table still in force beside
Housecarl's. The docs say to disable nftables.service but not stop it.
- A raw rule with other fields set is refused (raw_conflict) instead of
silently ignoring them; the rule dialog's nftables section hides what
it replaces, and the importer's raw rules carry only their text.
- A dynamic set with configured entries is refused
(set_dynamic_entries): they were silently ignored. The set dialog
shows entries or the entry timeout, as fits.
- The rule dialog's chain choices are just the chains' names.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.0's third release candidate. Since rc.2: changes made over
the network are confirmed by the client that made them, once it reaches
Housecarl again over a new connection (a change that cuts it off rolls
back by itself), and the rule dialog keeps its less used parts behind
"+" buttons. make test (with nft 1.1.3) and make e2e (136 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A change made over the network answers with a one-time confirm_token
and closes its connection (HTTP/2: a GOAWAY). The web UI and hc send the
token straight back to /confirm, which accepts it only for the newest
change, from the same user and API token, the same address, and over a
new connection: proof that the client can still reach the API through
the new ruleset (an established connection would get through anyway). A
change that cuts its client off can't be confirmed so, and rolls back by
itself. The setting manual_confirm (hc settings set --auto-confirm off)
and hc --no-confirm leave confirming to a person. Changes through the
local socket still need no confirmation. e2e: 136 checks, among them a
lockout change rolled back without anyone confirming.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
The new rule window shows chain, zones, addresses, services, family,
action, log and comment; connection state, time window, rate limit,
quota, connection limit and raw nftables open with "+" buttons (and
close with ✕, which unsets them). Editing a rule opens what it uses.
Group addresses appears only when a per-address limit, quota or
connection limit is set. Clearer help for connection state and status.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.0's second release candidate. Since rc.1: nftables maps
are imported; changes can be staged in changesets, reviewed with the
ruleset's diff and applied together (the web UI's default, as in Jarl);
bandwidth limits and quotas (per rule or per address, reset on a
schedule, kept across reboots); and generic examples. make test (with
nft 1.1.3) and make e2e (120 checks) pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Changesets, as in Jarl: configuration changes are operations that can be
staged in a changeset, checked as they are added (validation and nft -c),
reviewed with the diff of the ruleset, and applied together as one
history entry, then on probation like any change made over the network.
The web UI collects edits for review by default (pending rows, a bar with
Review and Apply now, a Changes page, a switch for live edits); hc stages
with -C ID or HOUSECARL_CHANGESET (checked like JARL_CHANGESET) and has
hc changeset create/list/show/diff/apply/discard/remove. Undo, import and
takeover refuse a changeset. --dry-run shows the ruleset's diff.
Bandwidth and quotas: rate limits in bytes, per source or destination;
quotas per rule or per address that reset daily, weekly, monthly on a
day, or by hand, with their usage carried across reloads, saved for
reboots, shown by hc quotas and on the rules page, and reset with hc rule
reset-quota. Rules that count traffic are checked before established
connections are accepted (so they see every packet) and can't accept.
Per-address limits group IPv6 by /64 by default (--group-v4/-v6).
Per-source rate meters use update. The importer turns meters, byte rates
and quotas into these fields.
The examples in the web UI, hc's help and the docs use documentation
addresses and generic names instead of the maintainer's network.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
A DNAT map (named or anonymous) becomes one port forward per element,
named after the map; a verdict map becomes one rule per element, in
place, with jumps inlined. A lookup matches one element at most, so the
expanded rules do the same. A named map that can't be expanded (keyed by
several fields) is left out with a note instead of a raw rule naming it,
which nftables would refuse. Test fixture made with nft 1.1.3.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl 0.1.0's first release candidate: an nftables firewall manager
with zones, address sets, services and ordered rules, IPv4 and IPv6, port
forwards with hairpin NAT and IPv6 pinholes, source NAT, redirects,
built-ins, probation for network changes, the ruleset at boot, hits and
the drop log, nftables import, a web UI, REST API and CLI. make test
(with nft 1.1.3), make e2e (71 checks) and the package test pass.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Zones, address sets (IPv4 and IPv6 mixed, dynamic sets with timeouts) and
services, ordered rules in the early, input, forward and output chains,
port forwards with hairpin NAT and IPv6 pinholes, source NAT, redirects,
and switchable built-ins (loopback, conntrack, ICMPv6, antispoofing, MSS
clamping, DHCPv6 client, flowtable). Every change is validated, checked
with nft -c and applied in one transaction to Housecarl's own table,
inet housecarl; changes made over the network roll back unless
confirmed, and the confirmed ruleset is loaded at boot by
housecarl-ruleset.service. An empty configuration applies nothing.
Also: hit counters and the drop log (nflog), 'hc import' of an existing
nftables ruleset and 'hc takeover', the hc CLI, the REST API and the web
UI, users, scoped tokens (sets:write:NAME), the audit log, the web UI's
certificate through Jarl, Debian packages, docs, unit tests with real
nft 1.1.3, and an e2e test with real traffic (71 checks).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Housecarl will be a firewall manager for nftables, built the way Jarl and
Steward are: housecarld (a daemon with a REST API and web UI), hc (the
CLI) and SQLite.
- The logo: a carved Nordic doorway in Jarl's blue (artwork/logo.svg),
with a small version without the carvings, lighter on dark
backgrounds. scripts/logo.py builds the web UI's copies and
scripts/banner.py the README banner.
- The HOUSECARL wordmark in Jarl's and Steward's angular letters, with
new H, O, U and C (assets/brand.js), and the UI's color tokens.
- housecarld and hc print their version; the Makefile, version package,
AGENTS.md, CHANGELOG and the design sketch (docs/design.md).
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>