Hermes-agent

plugins/platforms/photon/sidecar/README.md

@@ -0,0 +1,52 @@
+# Photon sidecar
+
+Small Node helper that bridges Hermes Agent to Photon's Spectrum SDK
+(`spectrum-ts`).  Hermes is Python; Photon has no public HTTP
+send-message endpoint today; replies therefore go through this sidecar.
+
+The sidecar:
+
+- runs `Spectrum({ projectId, projectSecret, providers: [imessage.config()] })`
+- exposes a loopback-only HTTP control channel for the Python adapter
+  to push send/typing requests (auth via `X-Hermes-Sidecar-Token`)
+- drains the inbound message stream so `spectrum-ts` keeps its
+  reconnect/heartbeat machinery alive (real inbound delivery is via
+  Photon's signed webhook hitting our Python aiohttp server)
+
+## Install
+
+```bash
+cd plugins/platforms/photon/sidecar
+npm install
+```
+
+The Hermes plugin's `hermes photon setup` command runs `npm install`
+here automatically.
+
+## Run standalone
+
+For debugging:
+
+```bash
+PHOTON_PROJECT_ID=... PHOTON_PROJECT_SECRET=... \
+PHOTON_SIDECAR_PORT=8789 PHOTON_SIDECAR_TOKEN=$(openssl rand -hex 16) \
+node index.mjs
+```
+
+In normal use, the Python adapter supervises this process — start,
+restart on crash, kill on shutdown — and never asks the user to run
+it by hand.
+
+## Why a sidecar at all?
+
+Photon publishes webhooks (inbound) but their docs state explicitly:
+
+> Pass `space.id` to `Space.send(...)` from a separate `spectrum-ts`
+> SDK instance to reply.  No public HTTP send endpoint exists today.
+
+— https://photon.codes/docs/webhooks/events
+
+When Photon ships an HTTP send endpoint, the plan is to retire this
+sidecar entirely and call it directly from Python.  The plugin's
+outbound code path is already isolated behind a single helper
+(`_sidecar_send` in `adapter.py`) to make that swap a one-file change.

plugins/platforms/photon/sidecar/index.mjs

@@ -0,0 +1,690 @@
+// Hermes Agent — Photon Spectrum sidecar
+//
+// Spawned by `plugins/platforms/photon/adapter.py` to bridge BOTH directions
+// of messaging to Photon's Spectrum platform via the `spectrum-ts` SDK (the
+// SDK is TypeScript-only, so a Node sidecar is unavoidable — there is no
+// Python SDK and no public HTTP message API).
+//
+// Inbound  (gRPC -> Hermes): the SDK's `app.messages` async iterator is a
+//   long-lived gRPC stream. We serialize each `[space, message]` to a
+//   normalized JSON event and stream it to the Python adapter over a
+//   loopback `GET /inbound` (NDJSON). We pause pulling from the stream while
+//   no consumer is attached so a backlog isn't pulled-and-lost before the
+//   gateway connects.
+// Outbound (Hermes -> gRPC): `/send` drives `space.send(...)`; `/typing`
+//   sends the documented `typing("start" | "stop")` content builder.
+//
+// Protocol (all requests require `X-Hermes-Sidecar-Token: ${TOKEN}`):
+//   - GET  /inbound    -> 200 NDJSON stream; one JSON event per line, blank
+//                         lines are heartbeats. One consumer at a time.
+//   - POST /healthz     -> {"ok": true}
+//   - POST /send        -> {"ok": true, "messageId": "..."}
+//       body: {"spaceId": "...", "text": "...",
+//              "format": "text" | "markdown" (default "text")}
+//   - POST /send-attachment -> {"ok": true, "messageId": "..."}
+//       body: {"spaceId": "...", "path": "...", "name": "..." | null,
+//              "mimeType": "..." | null, "caption": "..." | null,
+//              "kind": "attachment" | "voice"}
+//   - POST /react       -> {"ok": true, "reactionId": "..." | null}
+//       body: {"spaceId": "...", "messageId": "<target msg id>",
+//              "emoji": "👀"}
+//   - POST /unreact     -> {"ok": true} | 400 soft failure
+//       body: {"spaceId": "...", "messageId": "<target msg id>",
+//              "reactionId": "..." | null (restart-recovery fallback)}
+//   - POST /typing      -> {"ok": true}
+//       body: {"spaceId": "...", "state": "start" | "stop"}
+//   - POST /shutdown    -> {"ok": true}; then process exits
+//
+// On SIGINT/SIGTERM the sidecar calls `app.stop()` (3s graceful) before
+// exiting. Logs go to stderr; Python supervises restart.
+//
+// Requires spectrum-ts 3.x — pinned exactly in package.json because the SDK
+// ships breaking majors; see README "Upgrading spectrum-ts".
+//
+// Env vars (required):
+//   PHOTON_PROJECT_ID      (== the project's spectrumProjectId)
+//   PHOTON_PROJECT_SECRET
+//   PHOTON_SIDECAR_PORT
+//   PHOTON_SIDECAR_TOKEN
+// Optional:
+//   PHOTON_SIDECAR_BIND    (default 127.0.0.1)
+//   PHOTON_SIDECAR_WATCH_STDIN  "1" = exit when stdin hits EOF (set by the
+//                          adapter, which holds our stdin pipe — parent-death
+//                          detection so a dead gateway can't orphan us)
+//   PHOTON_TELEMETRY       enable Spectrum SDK telemetry ("true"/"1"/"on"/"yes";
+//                          default off — toggle with `hermes photon telemetry`)
+
+import http from "node:http";
+import crypto from "node:crypto";
+import { once } from "node:events";
+
+const projectId = process.env.PHOTON_PROJECT_ID;
+const projectSecret = process.env.PHOTON_PROJECT_SECRET;
+const port = parseInt(process.env.PHOTON_SIDECAR_PORT || "8789", 10);
+const bind = process.env.PHOTON_SIDECAR_BIND || "127.0.0.1";
+const sharedToken = process.env.PHOTON_SIDECAR_TOKEN;
+const telemetry = /^(1|true|yes|on)$/i.test(
+  (process.env.PHOTON_TELEMETRY || "").trim()
+);
+
+// Inbound binary content is read into memory and base64-inlined on the NDJSON
+// event so the Python adapter can cache the real bytes (and the agent can see
+// images / transcribe voice). Cap the size we inline — above it we forward
+// metadata only and the adapter surfaces a text marker, so one large clip can't
+// balloon a single NDJSON line. Override via PHOTON_MAX_INLINE_ATTACHMENT_BYTES.
+const MAX_INLINE_ATTACHMENT_BYTES =
+  Number(process.env.PHOTON_MAX_INLINE_ATTACHMENT_BYTES) || 20 * 1024 * 1024;
+const DM_CHAT_GUID_RE = /^any;-;(\+\d{6,})$/;
+const E164_RE = /^\+\d{6,}$/;
+const MAX_KNOWN_SPACES = 2048;
+const MAX_KNOWN_MESSAGES = 1024;
+const MAX_REACTION_HANDLES = 512;
+
+if (!projectId || !projectSecret || !sharedToken) {
+  console.error(
+    "photon-sidecar: PHOTON_PROJECT_ID, PHOTON_PROJECT_SECRET and " +
+      "PHOTON_SIDECAR_TOKEN must all be set."
+  );
+  process.exit(2);
+}
+
+// Lazy-load spectrum-ts so a missing install fails with a clear message
+// instead of a cryptic module-resolution error during import.
+let Spectrum,
+  imessage,
+  attachment,
+  voice,
+  spectrumText,
+  spectrumMarkdown,
+  spectrumTyping;
+try {
+  ({
+    Spectrum,
+    attachment,
+    voice,
+    text: spectrumText,
+    markdown: spectrumMarkdown,
+    typing: spectrumTyping,
+  } = await import("spectrum-ts"));
+  ({ imessage } = await import("spectrum-ts/providers/imessage"));
+} catch (e) {
+  console.error(
+    "photon-sidecar: spectrum-ts is not installed. Run `npm install` " +
+      "inside plugins/platforms/photon/sidecar/. Original error: " +
+      (e && e.stack ? e.stack : String(e))
+  );
+  process.exit(3);
+}
+
+const app = await Spectrum({
+  projectId,
+  projectSecret,
+  providers: [imessage.config()],
+  options: { flattenGroups: true },
+  telemetry,
+});
+
+// ---------------------------------------------------------------------------
+// Inbound: forward `app.messages` (gRPC stream) to the Python consumer.
+
+// At most one Python consumer is attached at a time (the gateway adapter).
+let consumerRes = null;
+let consumerWaiters = [];
+const knownSpaces = new Map();
+// Inbound Message objects by id, so /react can usually skip a
+// `space.getMessage` round trip when tapping back on a recent message.
+const knownMessages = new Map();
+// One reaction handle per reacted-to message (key `${spaceId}\0${messageId}`,
+// value {emoji, handle}) — mirrors iMessage's one-tapback-per-sender
+// semantics; a new /react on the same target overwrites the slot. The handle
+// is the outbound reaction Message returned by `target.react()`, kept so
+// /unreact can `unsend()` it later.
+const reactionHandles = new Map();
+
+function lruSet(map, key, value, cap) {
+  if (map.has(key)) map.delete(key);
+  map.set(key, value);
+  if (map.size > cap) {
+    const oldest = map.keys().next().value;
+    if (oldest !== undefined) map.delete(oldest);
+  }
+}
+
+function rememberKnownSpace(id, space) {
+  if (!id || typeof id !== "string" || !space) return;
+  lruSet(knownSpaces, id, space, MAX_KNOWN_SPACES);
+}
+
+function rememberKnownMessage(message) {
+  const id = message?.id;
+  if (!id || typeof id !== "string") return;
+  lruSet(knownMessages, id, message, MAX_KNOWN_MESSAGES);
+}
+
+function phoneTargetFromSpaceId(spaceId) {
+  if (typeof spaceId !== "string") return null;
+  if (E164_RE.test(spaceId)) return spaceId;
+  const dmGuid = spaceId.match(DM_CHAT_GUID_RE);
+  return dmGuid ? dmGuid[1] : null;
+}
+
+function rememberInboundSpace(space, message) {
+  const msgSpace = message?.space || {};
+  const ids = [space?.id, msgSpace.id];
+  for (const id of ids) {
+    rememberKnownSpace(id, space);
+    const phone = phoneTargetFromSpaceId(id);
+    if (phone) rememberKnownSpace(phone, space);
+  }
+}
+
+function waitForConsumer() {
+  if (consumerRes) return Promise.resolve();
+  return new Promise((resolve) => consumerWaiters.push(resolve));
+}
+
+function setConsumer(res) {
+  consumerRes = res;
+  const waiters = consumerWaiters;
+  consumerWaiters = [];
+  for (const resolve of waiters) resolve();
+}
+
+function clearConsumer(res) {
+  if (consumerRes === res) consumerRes = null;
+}
+
+// Write one NDJSON line to the active consumer. Blocks until a consumer is
+// connected; if the write fails (consumer vanished mid-flight) we wait for a
+// new consumer and retry, so a message is never silently dropped here.
+async function deliver(line) {
+  for (;;) {
+    await waitForConsumer();
+    const res = consumerRes;
+    if (!res) continue;
+    try {
+      const flushed = res.write(line + "\n");
+      if (!flushed) await once(res, "drain");
+      return;
+    } catch {
+      clearConsumer(res);
+    }
+  }
+}
+
+async function normalizeBinaryContent(content) {
+  const meta = {
+    type: content.type,
+    id: content.id ?? null,
+    name: content.name ?? null,
+    mimeType: content.mimeType ?? null,
+    size: typeof content.size === "number" ? content.size : null,
+  };
+  if (content.type === "voice" && typeof content.duration === "number") {
+    meta.duration = content.duration;
+  }
+
+  // Read the bytes eagerly and base64-inline them as `data` so the Python
+  // adapter can cache the real file (the agent then sees images and can run
+  // STT on voice notes). Spectrum content objects may not outlive this stream
+  // iteration, so a lazy/on-demand fetch isn't safe. Over-cap content (when
+  // size is known up front) is forwarded as metadata only and the adapter falls
+  // back to a text marker. A read failure must never break the inbound loop.
+  const label = `${content.type} ${meta.name ?? meta.id ?? "(unnamed)"}`;
+  if (meta.size !== null && meta.size > MAX_INLINE_ATTACHMENT_BYTES) {
+    console.error(
+      `photon-sidecar: ${label} (${meta.size} bytes) ` +
+        `exceeds inline cap ${MAX_INLINE_ATTACHMENT_BYTES}; forwarding metadata only`
+    );
+    return meta;
+  }
+  if (typeof content.read === "function") {
+    try {
+      const buf = await content.read();
+      // Guard the case where size was unknown but the bytes turn out to be
+      // over the cap.
+      if (buf && buf.length > MAX_INLINE_ATTACHMENT_BYTES) {
+        console.error(
+          `photon-sidecar: ${label} (${buf.length} bytes) ` +
+            `exceeds inline cap after read; forwarding metadata only`
+        );
+        return meta;
+      }
+      meta.data = Buffer.from(buf).toString("base64");
+      meta.encoding = "base64";
+    } catch (e) {
+      console.error(
+        `photon-sidecar: failed to read ${content.type} bytes ` +
+          "(forwarding metadata only): " +
+          (e && e.stack ? e.stack : String(e))
+      );
+    }
+  }
+  return meta;
+}
+
+async function normalizeContent(content) {
+  if (!content || typeof content !== "object") {
+    return { type: "unknown" };
+  }
+  if (content.type === "text") {
+    return { type: "text", text: content.text || "" };
+  }
+  if (content.type === "attachment" || content.type === "voice") {
+    return await normalizeBinaryContent(content);
+  }
+  if (content.type === "reaction") {
+    return {
+      type: "reaction",
+      emoji: content.emoji || "",
+      targetMessageId: content.target?.id ?? null,
+      // Lets Python gate "is this a reaction to one of MY messages" without
+      // tracking every outbound id. May be null if the provider doesn't
+      // hydrate the target — Python falls back to its own sent-id cache.
+      targetDirection: content.target?.direction ?? null,
+    };
+  }
+  return { type: content.type || "unknown" };
+}
+
+async function normalizeEvent(space, message) {
+  try {
+    const msgSpace = message.space || {};
+    const ts = message.timestamp;
+    return {
+      messageId: message.id ?? null,
+      platform: message.platform || space.__platform || "iMessage",
+      space: {
+        id: space.id ?? msgSpace.id ?? null,
+        // iMessage spaces carry `type` ("dm"|"group") and `phone` directly.
+        type: space.type ?? msgSpace.type ?? "dm",
+        phone: space.phone ?? msgSpace.phone ?? null,
+      },
+      sender: { id: message.sender ? message.sender.id : null },
+      content: await normalizeContent(message.content),
+      timestamp:
+        ts instanceof Date ? ts.toISOString() : ts ? String(ts) : null,
+    };
+  } catch (e) {
+    console.error(
+      "photon-sidecar: failed to normalize inbound message: " + String(e)
+    );
+    return null;
+  }
+}
+
+// spectrum-ts handles in-session gRPC reconnects internally, but if the async
+// iterator itself throws or ends, this consumer would stop forever. Wrap it in
+// a re-subscribe loop with capped exponential backoff + jitter so inbound
+// always recovers (the adapter dedupes any catch-up replay).
+(async () => {
+  let backoff = 1000;
+  for (;;) {
+    try {
+      for await (const [space, message] of app.messages) {
+        backoff = 1000; // healthy traffic — reset
+        // Only forward inbound messages (ignore our own outbound echoes).
+        if (message && message.direction && message.direction !== "inbound") {
+          continue;
+        }
+        rememberInboundSpace(space, message);
+        rememberKnownMessage(message);
+        const event = await normalizeEvent(space, message);
+        if (!event) continue;
+        await deliver(JSON.stringify(event));
+      }
+      console.error("photon-sidecar: inbound stream ended — re-subscribing");
+    } catch (e) {
+      console.error(
+        "photon-sidecar: inbound stream errored — restarting: " +
+          (e && e.message ? e.message : String(e))
+      );
+    }
+    await new Promise((r) =>
+      setTimeout(r, backoff + Math.random() * backoff * 0.2)
+    );
+    backoff = Math.min(backoff * 2, 30000);
+  }
+})();
+
+// ---------------------------------------------------------------------------
+// HTTP control + inbound server (loopback only).
+
+// Control-message bodies are tiny; cap the body so a compromised local peer
+// can't OOM the sidecar by streaming an unbounded request (defence-in-depth on
+// the loopback channel).
+const MAX_BODY_BYTES = 2 * 1024 * 1024; // 2 MiB
+async function readBody(req) {
+  const chunks = [];
+  let size = 0;
+  for await (const chunk of req) {
+    size += chunk.length;
+    if (size > MAX_BODY_BYTES) {
+      req.destroy();
+      throw new Error("request body too large");
+    }
+    chunks.push(chunk);
+  }
+  const raw = Buffer.concat(chunks).toString("utf-8");
+  if (!raw) return {};
+  try {
+    return JSON.parse(raw);
+  } catch (e) {
+    throw new Error("invalid JSON body");
+  }
+}
+
+function unauthorized(res) {
+  res.statusCode = 401;
+  res.setHeader("Content-Type", "application/json");
+  res.end(JSON.stringify({ ok: false, error: "unauthorized" }));
+}
+
+function badRequest(res, msg) {
+  res.statusCode = 400;
+  res.setHeader("Content-Type", "application/json");
+  res.end(JSON.stringify({ ok: false, error: msg }));
+}
+
+function serverError(res) {
+  res.statusCode = 500;
+  res.setHeader("Content-Type", "application/json");
+  // Don't leak stack traces or raw exception text to the caller — even
+  // though we listen on loopback, the supervisor logs the real error
+  // and the client only needs a generic failure signal.
+  res.end(JSON.stringify({ ok: false, error: "internal sidecar error" }));
+}
+
+function ok(res, data) {
+  res.statusCode = 200;
+  res.setHeader("Content-Type", "application/json");
+  res.end(JSON.stringify({ ok: true, ...data }));
+}
+
+function handleInbound(req, res) {
+  res.statusCode = 200;
+  res.setHeader("Content-Type", "application/x-ndjson");
+  res.setHeader("Cache-Control", "no-store");
+  res.setHeader("Connection", "keep-alive");
+  // One consumer at a time — a fresh connection (e.g. after a reconnect)
+  // supersedes the previous one.
+  if (consumerRes && consumerRes !== res) {
+    try {
+      consumerRes.end();
+    } catch {
+      /* ignore */
+    }
+  }
+  setConsumer(res);
+  // Heartbeat keeps the socket warm through idle periods and lets the Python
+  // side detect a dead pipe promptly.
+  const heartbeat = setInterval(() => {
+    try {
+      res.write("\n");
+    } catch {
+      /* ignore */
+    }
+  }, 25000);
+  const cleanup = () => {
+    clearInterval(heartbeat);
+    clearConsumer(res);
+  };
+  req.on("close", cleanup);
+  req.on("aborted", cleanup);
+  res.on("error", cleanup);
+}
+
+async function resolveSpace(spaceId) {
+  const cached = knownSpaces.get(spaceId);
+  if (cached) return cached;
+
+  const im = imessage(app);
+  const phoneTarget = phoneTargetFromSpaceId(spaceId);
+  let space = null;
+
+  // A bare E.164 phone number addresses a DM, so callers can pass just
+  // "+1..." (e.g. PHOTON_HOME_CHANNEL for cron delivery) instead of an opaque
+  // inbound space id. Photon also represents DM chat ids as `any;-;+1...`;
+  // normalize those through the same path. `space.create` accepts the raw
+  // phone string directly.
+  if (phoneTarget) {
+    try {
+      space = await im.space.create(phoneTarget);
+    } catch (e) {
+      console.error(
+        "photon-sidecar: phone->DM space.create failed: " +
+          (e && e.stack ? e.stack : String(e))
+      );
+    }
+  }
+  // Anything else — typically an opaque group GUID — is rehydrated from the
+  // persisted id via `space.get`, so group spaces stay reachable after a
+  // sidecar restart even before any fresh inbound message in that group.
+  if (!space) {
+    try {
+      space = await im.space.get(spaceId);
+    } catch (e) {
+      console.error(
+        "photon-sidecar: space.get failed: " +
+          (e && e.stack ? e.stack : String(e))
+      );
+    }
+  }
+  if (!space) throw new Error(`unable to resolve space id ${spaceId}`);
+
+  rememberKnownSpace(spaceId, space);
+  if (phoneTarget) rememberKnownSpace(phoneTarget, space);
+  rememberKnownSpace(space?.id, space);
+  return space;
+}
+
+// Constant-time token comparison — don't leak the token via `!==` timing.
+const _tokenBuf = Buffer.from(sharedToken);
+function tokenOk(header) {
+  if (typeof header !== "string") return false;
+  const h = Buffer.from(header);
+  return h.length === _tokenBuf.length && crypto.timingSafeEqual(h, _tokenBuf);
+}
+
+const server = http.createServer(async (req, res) => {
+  if (!tokenOk(req.headers["x-hermes-sidecar-token"])) {
+    return unauthorized(res);
+  }
+  // Long-lived inbound NDJSON stream.
+  if (req.method === "GET" && req.url === "/inbound") {
+    return handleInbound(req, res);
+  }
+  if (req.method !== "POST") {
+    res.statusCode = 405;
+    return res.end();
+  }
+  try {
+    if (req.url === "/healthz") {
+      return ok(res, {});
+    }
+    if (req.url === "/shutdown") {
+      ok(res, {});
+      setTimeout(() => process.kill(process.pid, "SIGTERM"), 50);
+      return;
+    }
+    const body = await readBody(req);
+    if (req.url === "/send") {
+      const { spaceId, text, format = "text" } = body || {};
+      if (!spaceId || typeof text !== "string") {
+        return badRequest(res, "spaceId and text are required");
+      }
+      if (format !== "text" && format !== "markdown") {
+        return badRequest(res, "format must be text or markdown");
+      }
+      const space = await resolveSpace(spaceId);
+      // iMessage renders markdown natively; spectrum-ts degrades it to
+      // readable plain text on platforms that don't.
+      const builder =
+        format === "markdown" ? spectrumMarkdown(text) : spectrumText(text);
+      const result = await space.send(builder);
+      return ok(res, { messageId: result?.id || null });
+    }
+    if (req.url === "/send-attachment") {
+      const { spaceId, path, name, mimeType, caption, kind } =
+        body || {};
+      if (!spaceId || typeof path !== "string" || !path) {
+        return badRequest(res, "spaceId and path are required");
+      }
+      const space = await resolveSpace(spaceId);
+
+      // spectrum-ts infers name + MIME from the file extension; pass
+      // overrides only when Hermes supplied them so a known-good
+      // inference isn't clobbered with an empty string.
+      const opts = {};
+      if (name) opts.name = name;
+      if (mimeType) opts.mimeType = mimeType;
+      const builder =
+        kind === "voice"
+          ? voice(path, Object.keys(opts).length ? opts : undefined)
+          : attachment(path, Object.keys(opts).length ? opts : undefined);
+
+      const result = await space.send(builder);
+
+      // iMessage delivers the caption as a separate bubble; send it
+      // after the media so the attachment renders first.
+      if (caption && typeof caption === "string") {
+        try {
+          await space.send(spectrumText(caption));
+        } catch (e) {
+          console.error(
+            "photon-sidecar: attachment sent but caption failed: " +
+              (e && e.stack ? e.stack : String(e))
+          );
+        }
+      }
+      return ok(res, { messageId: result?.id || null });
+    }
+    if (req.url === "/react") {
+      const { spaceId, messageId, emoji } = body || {};
+      if (!spaceId || !messageId || typeof emoji !== "string" || !emoji) {
+        return badRequest(res, "spaceId, messageId and emoji are required");
+      }
+      const space = await resolveSpace(spaceId);
+      const target =
+        knownMessages.get(messageId) ?? (await space.getMessage(messageId));
+      if (!target) {
+        return badRequest(res, "message not found");
+      }
+      const handle = await target.react(emoji);
+      if (!handle) {
+        return badRequest(res, "reactions not supported on this platform");
+      }
+      lruSet(
+        reactionHandles,
+        `${spaceId}\u0000${messageId}`,
+        { emoji, handle },
+        MAX_REACTION_HANDLES
+      );
+      return ok(res, { reactionId: handle.id ?? null });
+    }
+    if (req.url === "/unreact") {
+      const { spaceId, messageId, reactionId } = body || {};
+      if (!spaceId || !messageId) {
+        return badRequest(res, "spaceId and messageId are required");
+      }
+      const key = `${spaceId}\u0000${messageId}`;
+      const slot = reactionHandles.get(key);
+      if (slot) {
+        await slot.handle.unsend();
+        reactionHandles.delete(key);
+        return ok(res, {});
+      }
+      // Restart-recovery: the live handle is gone, so try rehydrating the
+      // reaction message by id and retracting it. Only outbound messages can
+      // be unsent — if the provider rehydrates it as inbound (or not at all)
+      // this throws, and that's an expected soft failure, not a sidecar bug:
+      // a stale tapback self-heals when the next /react replaces it.
+      if (reactionId) {
+        try {
+          const space = await resolveSpace(spaceId);
+          const msg = await space.getMessage(reactionId);
+          if (msg) {
+            await space.unsend(msg);
+            return ok(res, {});
+          }
+        } catch (e) {
+          console.error(
+            "photon-sidecar: best-effort unreact failed: " +
+              (e && e.message ? e.message : String(e))
+          );
+        }
+        return badRequest(res, "reaction not removable");
+      }
+      return badRequest(res, "no tracked reaction for message");
+    }
+    if (req.url === "/typing") {
+      const { spaceId, state = "start" } = body || {};
+      if (!spaceId) return badRequest(res, "spaceId is required");
+      if (state !== "start" && state !== "stop") {
+        return badRequest(res, "state must be start or stop");
+      }
+      const space = await resolveSpace(spaceId);
+      await space.send(spectrumTyping(state));
+      return ok(res, {});
+    }
+    res.statusCode = 404;
+    res.setHeader("Content-Type", "application/json");
+    return res.end(JSON.stringify({ ok: false, error: "not found" }));
+  } catch (e) {
+    console.error(
+      "photon-sidecar: handler error: " +
+        (e && e.stack ? e.stack : String(e))
+    );
+    // serverError() intentionally returns a generic message — see its
+    // body for the rationale.
+    return serverError(res);
+  }
+});
+
+server.listen(port, bind, () => {
+  console.error(`photon-sidecar: listening on ${bind}:${port}`);
+});
+
+let stopping = false;
+async function shutdown(signal) {
+  // Re-entry guard: stdin EOF, a signal and /shutdown can all fire together
+  // during one teardown.
+  if (stopping) return;
+  stopping = true;
+  console.error(`photon-sidecar: received ${signal}, stopping...`);
+  try {
+    await Promise.race([
+      app.stop(),
+      new Promise((resolve) => setTimeout(resolve, 3000)),
+    ]);
+  } catch (e) {
+    console.error("photon-sidecar: app.stop() failed: " + String(e));
+  }
+  server.close(() => process.exit(0));
+  setTimeout(() => process.exit(1), 500).unref();
+}
+
+process.on("SIGINT", () => shutdown("SIGINT"));
+process.on("SIGTERM", () => shutdown("SIGTERM"));
+
+// Lifetime binding to the parent. The adapter spawns us with stdin as a pipe
+// it holds open; EOF means the gateway process is gone — including hard
+// deaths (crash, SIGKILL) where no signal and no /shutdown ever reaches us.
+// Without this, an orphaned sidecar squats the port and keeps consuming the
+// inbound gRPC stream, and every replacement spawn dies on EADDRINUSE.
+// Opt-in via env so manual `node index.mjs` runs aren't affected.
+if (process.env.PHOTON_SIDECAR_WATCH_STDIN === "1") {
+  process.stdin.resume();
+  process.stdin.on("end", () => shutdown("stdin EOF (parent exited)"));
+  process.stdin.on("error", () => shutdown("stdin error (parent exited)"));
+}
+
+// Don't let a stray promise rejection take the process down silently — handlers
+// catch their own errors, so log and keep serving (Python supervises restart on
+// a real fatal exit).
+process.on("unhandledRejection", (reason) => {
+  console.error(
+    "photon-sidecar: unhandledRejection: " +
+      (reason && reason.stack ? reason.stack : String(reason))
+  );
+});

plugins/platforms/photon/sidecar/package.json

@@ -0,0 +1,24 @@
+{
+  "name": "@hermes-agent/photon-sidecar",
+  "private": true,
+  "version": "0.3.0",
+  "description": "Spectrum-ts bridge for the Hermes Agent Photon platform plugin.",
+  "type": "module",
+  "main": "index.mjs",
+  "scripts": {
+    "start": "node index.mjs"
+  },
+  "engines": {
+    "node": ">=18.17"
+  },
+  "dependencies": {
+    "spectrum-ts": "3.1.0"
+  },
+  "overrides": {
+    "protobufjs": "8.6.1",
+    "@opentelemetry/otlp-transformer": "0.218.0",
+    "@opentelemetry/otlp-exporter-base": "0.218.0",
+    "@opentelemetry/exporter-trace-otlp-http": "0.218.0",
+    "@opentelemetry/exporter-logs-otlp-http": "0.218.0"
+  }
+}