Imported from marcus/sidecar (.claude/skills/port-herdr-integration/SKILL.md). Install upstream with npx skills add marcus/sidecar --skill port-herdr-integration. Copyright stays with the author.

Porting one Herdr integration

Sidecar installs its own hook, plugin and extension assets into other agents' configuration so those agents report their lifecycle state and their session identity back to Sidecar. The knowledge in those assets comes from Herdr, which ships seventeen of them. A port takes one provider's knowledge, keeps it verbatim, replaces Herdr's transport with Sidecar's, and lands it behind the same guards every existing adapter passes.

This is a procedure. Work through it in order for one provider at a time. Every step names the file to open and the test that gates it.

0. How Sidecar mirrors Herdr

Four things hold the mirror in place. Read them before you write anything.

The vendored tree. internal/agentintegration/upstream/<dir>/ holds byte-for-byte copies of Herdr's src/integration/assets. Nothing installs them and no runtime path reads them; they exist so re-porting a provider is a review of a diff rather than a fresh reading. internal/agentintegration/upstream/herdr-agent-state.test.ts at the root of that tree is upstream's own test, and its payloads are where your fixtures come from.

The lock. internal/agentintegration/upstream.lock.json pins every vendored file by SHA-256 and records each provider's HERDR_INTEGRATION_VERSION. It is keyed by Herdr's agent id, which is not always the directory name: agy is the id and antigravity_cli is the directory. TestVendoredIntegrationAssetsMatchLock fails if a vendored byte changes without a matching lock entry, so never hand-edit anything under upstream/.

The provenance record. internal/agentintegration/portedfrom.go holds one PortedFrom row per shipped asset: the Sidecar provider id, the Herdr agent id (UpstreamID, which must match the lock's key), the directory, the upstream version the port was written against, the commit, and prose evidence. It is Go data rather than a header comment because several Sidecar assets are Go values with no file to put a header in. TestEveryAdapterRecordsWhatItWasPortedFrom fails if an adapter ships without a row.

The sync tool and the weekly review. internal/tools/herdrsync re-vendors the tree, rewrites the lock, and renders internal/agentactivity/manifests/report.md. .github/workflows/herdr-sync.yml runs it every Monday, pushes bot/herdr-sync, and puts that report into the pull request body.

go run ./internal/tools/herdrsync performs a real sync. It fetches from Herdr and overwrites the vendored manifest and integration trees in your working directory. Do not run it to "see what it does". Read internal/agentactivity/manifests/report.md, and drive the renderer from tests when you need to see output. Name the package explicitly if you ever must run it, and never glob ./internal/tools/..., which expands to the sync tool and syncs.

1. Read the sync report to see which provider moved

Open internal/agentactivity/manifests/report.md and find ## Integration assets. It has two halves.

The table has one row per vendored provider: Agent | Asset directory | Version | Previous | Change | Sidecar port. The Change column says unchanged, **bumped**, **rolled back**, added or first sync. The Sidecar port column is derived from PortedFromRecords() at render time and reads either `<provider>` from version N or not ported.

Then ### Upstream changes since each Sidecar port gives, per ported provider, the diff between the upstream bytes at the commit the port was written from and the bytes just vendored. It diffs bytes, not version numbers, so a file upstream edited without bumping still shows. A file it could not read says was **not compared**; that is a comparison that did not happen and never evidence that anything changed.

Two traps:

• The committed report.md is a snapshot, not a live view. It is written only by a real sync run, so between syncs it is as stale as the last run. If it says not ported for a provider that has an adapter, believe PortedFromRecords() and not the file. TestARenderedReportNeverCallsAPortedProviderUnported in internal/tools/herdrsync/herdrsync_test.go renders the section against the embedded lock and the real records, so the next sync is guaranteed truthful; the committed file catches up when the workflow next runs. Do not regenerate it by hand.
• Everything below the table is bounded at integrationDiffSectionBudget (600 lines) so the report fits GitHub's pull request body limit. A diff elided there is named, not dropped.

The weekly review already surfaces this for you: internal/agentintegration/upstream is in the workflow's change-detection paths and in the paths it commits to the sync branch, so a ported provider's asset diff appears twice, as raw file changes on the branch and as rendered diffs in the pull request body.

2. Choose the port shape

There are three, and the choice is decided by where the provider's knowledge lives upstream, not by preference.

Shape A: entry in the provider's config file

Use it when Herdr's knowledge is a table in its Rust rather than in a shipped script: src/integration/mod.rs holds (event, matcher, action) rows, and the asset upstream ships is a thin shell shim that only gates on HERDR_ENV and writes a socket frame. There is nothing in that shim worth porting, because sidecar agent report is the gate for a hook surface and --hook-stdin reads the payload with a bounded reader. So the port is the table, rendered into the provider's own configuration file.

Reference: internal/agentintegration/kimi_install.go with kimi.go and kimi_test.go. Twelve rows, a fenced marker region in config.toml, a TOML parser used as a read-only oracle at both ends of every edit, and a golden checksum taken over the rendered block because there is no asset file. TestKimiFiresExactlyOneHookPerEvent exists because Kimi runs every matching hook in parallel, so two rows matching one event would be two report processes racing.

The second reference is Mastra Code, merged and on main: internal/agentintegration/mastracode_install.go with mastracode.go and mastracode_test.go, and its fixtures under internal/agentintegration/testdata/mastracode/. Eleven rows into ~/.mastracode/hooks.json, a millisecond timeout, || true on the three blocking events, and one row whose event moved because the live proof found upstream binding on a payload that carries a constructor placeholder rather than a thread id.

For the most compact list there is of what a port touches, run git log --stat over the mastracode commits (git log --stat --grep mastracode) and read the file names rather than the diff.

Shape B: a dropped file the provider loads

Use it when the knowledge is in a JS or TS asset upstream ships: a plugin, an extension, a Python package. The port is a Sidecar asset under internal/agentintegration/assets/<provider>/ whose provider half is upstream's behaviour kept verbatim and whose transport half is swapped.

References, and each directory has the same five parts:

The five parts of an asset directory:

1. sidecar-lifecycle.js (or the provider's own name) is the shipped bytes. Its first line carries the ownership marker.
2. A Go mirror beside it in the package root: opencode.go, pi.go, kilo.go, omp.go. It implements the same mapping in Go so Sidecar can reason about the asset without running node.
3. ordering-harness.mjs records the argv every real spawn produces. internal/cli's argv corpus reads it.
4. replay-harness.mjs drives the shipped JavaScript over a fixture file.
5. exports-harness.mjs checks the module's shape against what the provider will load. package.json makes the directory a module. Pi adds reinstantiate-harness.mjs for its reload path.

The fixtures are .tsv files under internal/agentintegration/testdata/<provider>/, one file per branch, each with a README.md saying what the columns mean. One fixture drives both implementations and they are compared action for action, which is the whole point of keeping a Go mirror: a divergence is a test failure rather than a field bug. OMP is the reference for a mapping that needs a clock, because a pure mapping may not call setTimeout: mapEvent emits schedule and cancel actions, the runtime owns the timer, and a fired timer re-enters the mapping as an ordinary event, so the .tsv can drive the debounce deterministically through both sides.

When the asset is not JavaScript. Hermes is the reference. Four of the shipped assets are JS and their harnesses are .mjs because node is what runs them; SIDECAR_REQUIRE_NODE=1 turns the skip into a failure in CI. Hermes is a Python package, and it is what a non-JS asset looks like when it is done: assets/hermes/__init__.py with plugin.yaml beside it, a Go mirror in hermes.go written exactly the way the JS mirrors are, and the harnesses as .py invoked through the interpreter the provider itself uses. assets/hermes/replay-harness.py drives the real register() over a fixture and reports the argv each spawn would have built, assets/hermes/argv-harness.py is the one that really spawns and feeds internal/cli's corpus, and both skip when python3 is absent unless SIDECAR_REQUIRE_PYTHON=1 says the run is one where a skip would hide a break. Read hermes_test.go for how the two halves are compared element for element.

When the asset is more than one file, or is a file plus a config edit. Hermes is the reference for that too. The other shape B ports drop exactly one file; Hermes writes __init__.py and plugin.yaml into <hermes dir>/plugins/sidecar-agent-state/ and adds one item to the plugins.enabled list in the user's config.yaml, which is shape B and shape A at once. Read hermes_install.go for the Assets() that returns three entries with two ownerships in it, hermes_config.go for the YAML line surgery, and hermes_test.go for what the suite has to prove.

Three things in that pair are the parts worth copying. The config edit is line surgery with a YAML parser used as a read-only oracle at both ends and never as a serializer, so the user's comments, anchors, quoting and key order survive byte for byte and a composed image that will not verify becomes a refusal with an empty op list rather than a partial write. Ownership of that line is its value rather than a marker comment, because hermes config set, hermes plugins enable and the setup wizard all round-trip the file through yaml.dump and drop every comment in it. And a half install reports nothing while looking present, so a state with the files but not the line is needs-repair rather than a lesser install. Only the shapes Hermes itself writes are edited: a flow sequence and a bare plugins list are both refused and named, because rewriting them would edit bytes outside Sidecar's own entry. Do not approximate any of it by rewriting the whole config file.

Shape C: a session-identity entry through the shared generic

Use it when Herdr's integration exists only to name the conversation occupying the pane. State still comes from the screen lane in both projects, so the port buys exact session binding and nothing else, which is what makes exact resume reliable.

Do not write a new adapter for this. internal/agentintegration/sessionhook.go is the whole lifecycle (inspect, status, the four verbs, the ownership gate, the backup, the refusals) driven by a sessionHookIntegration descriptor. Eight providers are instances of it: Antigravity, Copilot, Cursor, grok, Devin, Droid, Qoder CLI and Qwen. What a provider contributes is data.

sessionHookIntegration fields, in the order you will fill them:

hookEntrySpec in internal/agentintegration/hookconfig.go carries the coordinates: namedBlocks, block, flat, commandKey, altCommandKeys, matcher, events, and canonical (every asset version ever shipped, so an older installed entry reads as outdated rather than foreign).

Read one adapter per sub-shape before writing yours:

• copilot_install.go, the flat handler array. Three fields differ from every other provider and none was invented: type: "command", the command under bash rather than command, and timeoutSec rather than timeout. altCommandKeys carries the Windows powershell spelling, read but never written.
• antigravity_install.go, the named block. hooks.json is keyed by hook name, blocks from every source merge, so the scan walks every top-level block. Sidecar owns sidecar. It also shows the ; printf '{}\n' suffix a provider that demands JSON on stdout needs.
• cursor_install.go, the minimal entry. Cursor documents {"command": ...} with no type, and its own generator emits one with a type, so the scan accepts both. It is also where newFileMembers exists: Cursor's "version": 1 goes into a file Sidecar creates and never into a user's.
• grok_install.go, the dedicated file. grok merges every <grok home>/hooks/*.json, so Sidecar writes sidecar.json rather than editing the user's. It still owns only the entry inside it: a hook a user added beside Sidecar's survives, and the file goes away only when Sidecar's entry was all it held.
• devin_install.go, the ordered event list. Upstream maps six events to the same session action because it trusts no single Devin event to carry the id, so events is a list; every other integration passes none and gets SessionStart.
• droid_install.go, the shadow file. ~/.factory/hooks.json makes settings.json's hooks key inert, so an entry Sidecar wrote would be correct, read as current, and never fire. Status inspects the shadow file and names it. It does not change the status and it does not edit that file.

hookconfig.go owns the scan that finds Sidecar's entries in a file somebody else owns. hookPayload in internal/cli reads both spellings of a session id, snake_case winning, so one --hook-stdin reader serves every provider; Devin is why, and grok's payload carries both.

Whether to honour a provider's config-dir override is decided by evidence, not by the variable's name. Follow the code path that reads the file:

An override is read with overrideDir, which tilde-expands and trims whitespace. The exception is a provider that refuses a relative path itself: ClaudeConfigHome deliberately does neither, because Claude refuses a config home that is not absolute, and OMP's PI_CODING_AGENT_DIR is path.resolved against a cwd Sidecar cannot know, so a relative or ~-prefixed value is refused rather than guessed at.

3. Read the provider half, row by row, against Herdr

Read, read-only, in /Users/marcus/code/herdr/src/integration/: targets.rs (where the provider reads its hooks or plugins, and which variable relocates that), registry.rs, actions.rs, config_edit.rs, mod.rs, tests.rs. Then read the vendored asset under upstream/<dir>/, and upstream.lock.json for the version you are porting from.

Keep the provider half verbatim in behaviour: which event maps to working, blocked, idle or a session reference; the ordering guards; the per-provider quirks. Then check every claim against a released build of the provider where you can, because the ports that went wrong went wrong here:

• Kilo's session.status carries an object whose type is the discriminator, and Herdr's kilo asset at version 4 only accepts a string, so it maps none of them on that release. Sidecar takes the fixed form Herdr's own opencode asset already had.
• Pi's turn completion is agent_settled, not agent_end: ctx.isIdle is false on agent_end and true three milliseconds later.
• OMP has no agent_settled at all, and Pi's guard is wrong in both directions there. Upstream's three guards replace it.

Where Herdr does something Sidecar will not, say so and say why. Sidecar's rules are stricter in two standing places: ownership by marker only, and refuse rather than overwrite.

4. Swap the transport half

Herdr's transport gates on HERDR_ENV and writes a JSON-RPC frame to HERDR_SOCKET_PATH. Sidecar's is:

const bin = process.env.SIDECAR_BIN
if (process.env.SIDECAR_MANAGED_SHELL !== "1" || !bin) return

then spawn $SIDECAR_BIN agent report ... for a state report, or $SIDECAR_BIN agent report-session for a session binding. internal/agentintegration/assets/opencode/sidecar-lifecycle.js and assets/pi/ are the reference translations.

report-session takes exactly one of --id ID, --path ABS_PATH, --clear or --hook-stdin, and they are mutually exclusive. Which one you use follows from the shape: a hook the provider hands a JSON payload on stdin uses --hook-stdin, and the bounded reader takes both spellings of the id for you; a plugin or extension already holding the value in process passes --id, because piping a payload you constructed yourself back through a parser buys nothing. Omit --source and the report gets OfficialSourceFor(kind), which is what makes it trusted and resumable, so name a source only if you deliberately want an untrusted one.

Five rules:

Never pass --seq. The store assigns sequences under the lock it already holds for the append. Upstream seeds a counter from Date.now() * 1000 because a socket bounds nothing; Sidecar's store bounds the field at MaxSequence = 1 << 40, so that seed sits about 1600x over the ceiling and every report is silently rejected, because reports spawn with stdio: "ignore" and nobody reads their exit codes. Omitting the field also makes the reload hazard the seed existed for structurally impossible.

Do not claim to be Herdr. No HERDR_* variables. Sidecar and Herdr nest, and claiming the other's identity is a real collision.

|| true on any hook event whose exit code the provider reads as a refusal. Mastra Code reads exit code 2 on PreToolUse, Stop and UserPromptSubmit as the hook refusing the agent's own work, so those three commands end || true. A hook surface must fail open: a Sidecar that is missing, refusing or slow may never change what the provider does. Antigravity gets the same guarantee a different way, because the ; printf '{}\n' it needs anyway means the exit status the provider sees is printf's.

Drop an upstream argument Sidecar's verbs do not have, rather than inventing a flag for it. Herdr's assets pass --session-start-source startup|new|resume and a --agent beside the pane id. report-session has neither and wants neither: a session id names the same conversation whether it arrived at startup, on resume, or after a compact, and the kind is --kind. Keep the provider's own branching if it gates whether to report (Hermes reports on_session_reset and pre_llm_call as well as on_session_start, and only for interactive platforms); drop only the label it would have carried.

Carry the attribution. Herdr is Apache-2.0; upstream/LICENSE and upstream/NOTICE travel with the copies, and a Sidecar asset carries the attribution header the existing assets carry.

5. Ownership: the marker and nothing else

An installer only ever removes changes Sidecar made, identified by the sidecar-integration: marker (markerToken in internal/agentintegration/install.go) and by nothing else. The same token reads with // in JavaScript and # in TOML.

Consequences you must implement rather than assume:

• Refuse when the parent directory is missing, if the provider's directory comes from an override that could point anywhere. Set setupHint; that is what turns a missing directory into a refusal instead of something install creates.
• Back up a user's file before editing it, the way the Claude installer does.
• Never copy an upstream uninstall that deletes on a marker that is not Sidecar's own. Herdr's uninstall_pi deletes without checking its marker and its remove_legacy_pi_extension_from_omp_dir deletes a file carrying HERDR_INTEGRATION_ID=pi. Neither is copied.
• Uninstall gives the file back byte for byte where it can. newFileMembers go away only when they are all that is left and each still holds the value Sidecar wrote.
• One hole is a limit rather than a bug and is recorded, not worked around: ownership reads the first word of a command, so a hook that wraps Sidecar's command in a script of the user's is not recognised. Adopting it would be worse.

sidecar agent integration status|install|uninstall|repair <provider> [--dry-run] [--json] must work through the existing CLI with no CLI change beyond registration.

6. Register the port everywhere

A port is not done until every one of these carries it. Sibling lanes port other providers concurrently, so append at the end of every list; that makes the merge trivial.

Shape C needs no argv-corpus entry of its own: SessionHookArgvCorpus() discovers the group by the promoted sessionHookIntegrationData() method, so a registered session-hook adapter is covered without being named. The same discovery drives sessionHookAdapters in sessionhook_test.go, so your provider joins nine shared tests the moment it is in DefaultAdapters(). Check that it did: if your provider does not appear as a subtest of TestASessionHookInstallsAndUninstallsCleanly, something about the embedding is wrong. That helper used to be a type switch naming four providers while the group had grown to eight, and four ports sat outside every assertion in the file until it was fixed.

Two more places a new adapter shows up and will need the assertion updated: internal/configui/agent_integrations_test.go carries the installed-provider list and count, and internal/agentsession/trust.go's Roots.For(kind) needs the provider's approved session-store roots if Sidecar is to bind a conversation by path.

7. Earn the tier; never copy it

Herdr's authority table says what is achievable. It is a target and nothing more.

Four tiers, defined in internal/agentlifecycle:

Capability.TierFor(status, providerInRange) polices every boundary, not only the top one, and it demotes rather than audits:

• full needs evidence: real-trace and every transition in FullLifecycleTransitions(): work_start, blocked_on_request, unblocked, turn_complete, cancelled, session_identity, process_exit. Otherwise it falls to advisory.
• advisory with evidence: none or an empty covered falls all the way to screen-fallback, because advisory still authors state when the screen is undecided.
• session-identity that does not actually cover session_identity falls out too.
• Only screen-fallback needs no evidence, because it asserts nothing.

So docs-only evidence may hold session-identity: the tier needs covered to name session_identity and needs evidence to be something other than none, and a port whose whole claim is "this entry reports the conversation id" can state that from a published contract. What it may not do is author state. That is why the honest shipping position differs by shape:

• A shape C port with a documented session event ships at session-identity on docs-only and is promoted to real-trace by one capture. Antigravity, Copilot and Cursor are that.
• A shape C port whose session event has not been seen at all ships at screen-fallback on docs-only, with the first known gap saying in its own words what a capture would change and that nothing else would have to. Devin, Droid and Qoder are that, each because its installer needs an account.
• A shape A or B port authors state, so it stays at screen-fallback until traces exist, then goes to advisory. full is usually unreachable for a port that keeps upstream's provider half.

Write the entry to internal/agentlifecycle/capabilities.json with schemaVersion, provider, source, assetVersion, tier, evidence, minProviderVersion, testedProviderRange, covered, knownGaps, orderingGuaranteed, sourceDoc and sourceVersionNote. knownGaps is prose and is where the port is honest: say which transitions are unreachable, whether each is unclaimed by choice or unclaimable, and what a future asset version would have to do to move it. Compare qwen (a ceiling reached by construction) and omp (two gaps that differ in direction) for the register.

Then write the prose companion section in docs/reference/agent-lifecycle-capability-matrix.md: a Source line naming the release read and the Herdr version, then a heading per finding, then a "Why <tier> is the ceiling" heading. Add your row to the Summary table.

TestHerdrAuthorityGaps closes a row only at full. sidecarTierRank gives advisory the same rank as screen-fallback, so a provider whose ceiling is advisory stays listed with its tier, and that is a pass. Do not tune the rule to empty the list.

8. Capture traces, if you can

A tier above session-identity-on-docs is earned by sanitized traces from a released provider version, checked in under internal/agentlifecycle/testdata/traces/<provider>/ with a provenance row in internal/agentlifecycle/testdata/README.md, and re-derived by tests in hooktrace_test.go. If the provider needs credentials the environment does not already export, stop, ship at the tier the rules allow, and say exactly why in the capability entry.

The six-column hook layout readHookTrace reads is offset_ms, event, session, turn, tool, fields. Sanitization is by construction: the tracer records event names, discriminators and payload field names, never prompt text, response text, tool arguments, results, paths, identifiers or environment values. Session ids are mapped to session-N placeholders inside the tracer process. A value is recorded only for a key whose vocabulary is closed by the provider's own source, and TestNoHookTraceCarriesAValue enforces valueBearingTraceKeys as an allowlist. Widening it is a deliberate act.

A trace whose value is an absence needs a # capture-window: 18s comment row when the interval is a watch; it needs none when the interval is delimited by two rows a reader can see.

There is no -update flag and there is not going to be one.

The cheapest requalification

For a session-identity port the whole claim is one event carrying one field. If the provider fires that event before authentication, the capture costs one process start rather than a credentialed model turn. Qwen does: the proof pane was sitting on its provider picker with no auth type selected when the hook had already run. Check this first for any untraced provider.

Proof-run hazards, every one of which was found the hard way

tmux. Read this before you type any tmux command.

• Never run tmux kill-server, at all, on any socket. A lane agent ran it and destroyed the maintainer's default server, and every live Sidecar and agent session on it, because $TMUX was inherited and the socket it named was the default one.
• unset TMUX at the top of every script that touches tmux, and in the env file every command sources. cmd/sidecar/main.go dispatches cli.Run before main unsets TMUX, deliberately and by comment, so a CLI-driven proof started inside a tmux pane talks to the socket named in $TMUX no matter what TMUX_TMPDIR says. scripts/tmux-drive.sh is unaffected because it launches the TUI.
• Every tmux call carries an explicit -S <absolute socket path>. Not -L, not an inherited default.
• Clean up only with tmux -S <socket> kill-session -t <name>, after listing the sessions on that socket to confirm what you created. Nothing else.
• Unix socket paths are capped near 104 bytes on macOS and the scratchpad path is too long. Use a short private directory such as /private/tmp/sc-<lane>-$(id -u) for the socket only; state and config still go under the scratchpad. Remove that directory afterwards.

Sidecar state. A private socket does nothing to isolate state. Set XDG_STATE_HOME under your scratch tree, SIDECAR_ISOLATED_STATE=1 (which makes the binary refuse to start rather than touch the real tree), and -config <scratch>/config.json. XDG_CONFIG_HOME moves nothing for Sidecar: config and state.json are $HOME-based, so -config is the only lever. Run ./scripts/tmux-drive.sh paths and confirm nothing resolves under ~/.local/state/sidecar or ~/.config/sidecar.

Scrub every SIDECAR_* variable, not only TMUX. SIDECAR_TMUX_SERVER leaking from an outer Sidecar shell made every hook report fail with lifecycle_invalid_context, silently, because a hook surface fails open.

macOS path_helper reorders PATH inside a new tmux pane, putting /etc/paths.d entries ahead of an inherited PATH, so a SIDECAR_BIN shim placed first loses to the Homebrew sidecar. Re-export PATH in the pane and check command -v sidecar before trusting a report.

The -config shim. An asset spawns $SIDECAR_BIN agent report with no -config, and ConfigPath() has no environment override, so a bare report under SIDECAR_ISOLATED_STATE=1 refuses. Use a one-line shim at SIDECAR_BIN that adds -config and passes argv through. Sidecar publishes SIDECAR_BIN from os.Executable with symlinks resolved, so the pane has to export the shim over the published value; being invoked as the shim is not enough.

Move every XDG directory as well as the provider's own override. A provider's config-dir override is a statement about where it reads, not a promise about where it writes. Kilo created its XDG default directories regardless of KILO_CONFIG_DIR, and one marker file landed in the maintainer's real ~/.config/kilo. Move HOME where you can; move XDG_CONFIG_HOME, XDG_DATA_HOME, XDG_STATE_HOME and XDG_CACHE_HOME always.

Export the provider's own directory override before the first integration status call, not after. detectProviderVersion runs <provider> --version, and a provider that initialises its home on any invocation would write into the real tree from that first probe.

Use a binary you built when proving anything that reads another process's environment. macOS gates the environment section of kern.procargs2 by binary: a SIP-protected platform binary such as /bin/sleep withholds it from everyone, same uid included, while an ordinary binary's is readable cross-process. A stand-in from /usr/bin reads empty for a reason that has nothing to do with the code, which is how a correct feature nearly got deleted as broken.

Uninstalling alone does not flip the lane. StoreSource.Evidence derives integrationStatus from the record, never from the installed files, so stored reports keep authority while integration status already says not-installed. The run must end as well; then you get authority=screen, fallbackReason=process_generation_mismatch.

Never set HERDR_ENV. With it set, Herdr's asset and Sidecar's would both claim the pane.

Install through the CLI, not by hand. sidecar agent integration install <provider> so the run proves the installer, its refusals and its mkdir.

Check $HOME afterwards. Create a marker file before the run and find ~ -maxdepth 3 -newer <marker> after it.

9. Run the guards

go build ./...
go vet ./...
go test ./internal/agentintegration ./internal/agentlifecycle ./internal/cli
go test -p 2 ./internal/tools/herdrsync    # never ./internal/tools/...

The guards that specifically gate a port:

10. Review checklist

Go through this before handing the port off.

• The provider half was read row by row against Herdr's own source, and every place Sidecar diverges is named with its evidence. A divergence with no stated reason is a transcription error waiting to be found.
• Every claim about the provider was checked against a released build where a released build could be run, and the entry says which claims are Herdr's word rather than the provider's.
• Goldens were not regenerated to make a test pass. A golden moving means the shipped bytes moved: bump the asset version constant first, then assetVersion in capabilities.json, then the checksum. bumpInstructions in asset_golden_test.go states the order.
• TestAPreviewsAfterStateMatchesWhatTheOpActuallyDoes passes for your provider. A preview that lies is worse than no preview.
• The symlink refusal covers your adapter: TestASymlinkedSessionIdentitySettingsFileIsRefusedUnwritten.
• The environment override is honoured only where the provider's own code path reads it, is tilde-expanded through overrideDir, and is not expanded where the provider itself refuses a relative path (Claude, OMP).
• --seq appears nowhere in the asset or the entry.
• The || true guard is on exactly the events whose exit code the provider reads as a refusal, and on no others.
• Ownership is by the sidecar-integration: marker and by nothing else, and uninstall gives a user's file back byte for byte.
• Every registry in step 6 has an appended entry, and the append is at the end of each list.
• A shape C port appears as a subtest of the nine sessionhook_test.go tests. If it does not, the embedding is wrong.
• The capability entry's tier is what the evidence earns, and TestHerdrAuthorityGaps is left alone.
• Any live proof used -S <absolute socket> on every tmux call, ran no kill-server of any kind, cleaned up with kill-session -t <name> only, and confirmed $HOME unchanged against a marker file.
• The plan, the capability matrix, CHANGELOG.md and the trace README all say what shipped.

11. What remains, as of Slice 7

No Herdr integration exists at all, so there is nothing to port: amp, muse, cline, kiro, maki, gemini. (gemini is additionally a declared-out family: Antigravity replaced it.)

Ported and traced: opencode (full), pi, kilo, kimi, omp, mastracode (all advisory, all at their ceiling), grok, qwen and hermes (session-identity, real-trace).

Ported and untraced, each pending an account or credentials this environment does not carry: devin, droid, qodercli (all at screen-fallback on docs-only; one SessionStart capture promotes each and nothing else changes), and antigravity, cursor, copilot (at session-identity on docs-only). cursor-agent stops at "Press any key to log in" once HOME moves and its hook loader has no override; agy opens a browser OAuth flow that times out; copilot is not installed anywhere Sidecar has surveyed.

Not ported yet: nothing. Every Herdr integration with a counterpart in Sidecar's catalog is ported. What is left is not porting work: it is a capture for each of the six untraced entries above, and subscription for the providers whose ceiling is higher than what their asset asks for.

Read docs/plans/implemented/herdr-parity-close-the-gap.md for the current state; its result subsections record what each port measured and are the reason most of this file exists.