fix(embed): use Array.isArray guard for agent data in OpenCode embed

[eibrahimov]

Summary

• Fixes the OpenCode embed crash: TypeError: .filter is not a function on sync.data.agent
• Fixes the web portal error: Unexpected token '<', "<!DOCTYPE"... is not valid JSON when fetching manifest.json

Root Cause

The embed is built from anomalyco/opencode@114eb4244 (OpenCode v1.2.15) but Spacebot runs against the installed OpenCode binary (tested with v1.2.20 and v1.3.0).

When the OpenCode server restarts (triggering a server.instance.disposed SSE event), the embed re-bootstraps and calls GET /agent. If the server responds with an empty body during startup, the SDK client (client.gen.ts) returns {data: {}} (empty object):

// SDK empty-body handling — returns {} not []
case "json": {
  const text = await response.text()
  data = text ? JSON.parse(text) : {}  // ← empty object for empty body
  break
}

The upstream code guards with x.data ?? [] (nullish coalescing), but ?? only catches null/undefined. An empty object {} is truthy and passes through. Calling .filter() on {} throws because plain objects lack Array methods.

Fix

Patches the embed build script (scripts/build-opencode-embed.sh step 2b) to apply Array.isArray() guards instead of ?? in two locations after git checkout but before the Vite build:

File	Before	After
local.tsx	sync.data.agent.filter(...)	(Array.isArray(sync.data.agent) ? sync.data.agent : []).filter(...)
bootstrap.ts	setStore("agent", x.data ?? [])	setStore("agent", Array.isArray(x.data) ? x.data : [])

Patches use perl -pi -e for macOS + Linux portability and are idempotent (safe to re-run).

OpenCode Versions Tested

Component	Version
Embed source (fork)	anomalyco/opencode@114eb4244 (v1.2.15-based)
Running binary	OpenCode v1.2.20 and v1.3.0 (via Homebrew)

Both versions return a valid JSON array from GET /agent, but during server restarts the response may be empty, triggering the SDK's {} fallback.

Test plan

• just preflight passes
• just gate-pr passes (697 tests, all green)
• Desktop app (Tauri): OpenCode embed loads without crash
• Web portal: manifest.json serves correctly, embed loads
• Verified Array.isArray guard in built bundle via grep
• CI passes

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 21e71135-5281-4fdd-858a-a4f5e7c934de

📥 Commits

Reviewing files that changed from the base of the PR and between b8a6bdd and 3c3b765.

📒 Files selected for processing (1)

• scripts/build-opencode-embed.sh

🚧 Files skipped from review as they are similar to previous changes (1)

• scripts/build-opencode-embed.sh

---

Walkthrough

The build script now injects two in-place compatibility patches into the vendored OpenCode embed source before dependency install/build, adding Array.isArray(...) guards when accessing agent data in two embed files and aborting if expected source patterns don't match.

Changes

Cohort / File(s)	Summary
Build script scripts/build-opencode-embed.sh	Adds two search-and-replace patch steps that apply and verify compatibility fixes in vendored embed source; aborts the build if expected patterns are not found.
Vendored OpenCode embed files src/context/local.tsx, src/context/global-sync/bootstrap.ts	Patch changes: wrap sync.data.agent.filter(...) with Array.isArray(sync.data.agent) ? sync.data.agent.filter(...) : [], and replace x.data ?? [] with Array.isArray(x.data) ? x.data : [] to guard against non-array responses.

Estimated code review effort

🎯 2 (Simple) | ⏱️ ~12 minutes

🚥 Pre-merge checks | ✅ 3

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title directly and specifically describes the main change: applying Array.isArray guards for agent data in the OpenCode embed, which is the primary fix.
Description check	✅ Passed	The description is comprehensive and clearly related to the changeset, explaining the root cause, the fix applied to the build script, affected files, and testing performed.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

_{✏️ Tip: You can configure your own custom pre-merge checks in the settings.}

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

---

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[coderabbitai]

🧹 Nitpick comments (1)

scripts/build-opencode-embed.sh (1)

114-125: Consider verifying that patches were actually applied.

The perl substitutions silently succeed even if zero matches are found. If upstream refactors these lines (e.g., renames sync.data.agent or changes the setStore call signature), the patches won't match and the build will proceed without the fix—causing the original crash to resurface at runtime.

🛡️ Suggested patch verification

 perl -pi -e \
   's/sync\.data\.agent\.filter\(/(Array.isArray(sync.data.agent) ? sync.data.agent : []).filter(/g' \
   "${LOCAL_TSX}"
-echo "[opencode-embed] Patched local.tsx: Array.isArray guard on agent filter"
+if grep -q 'Array\.isArray(sync\.data\.agent)' "${LOCAL_TSX}"; then
+  echo "[opencode-embed] Patched local.tsx: Array.isArray guard on agent filter"
+else
+  echo "[opencode-embed] ERROR: local.tsx patch did not apply — upstream may have changed."
+  exit 1
+fi

 perl -pi -e \
   's/input\.setStore\("agent",\s*x\.data\s*\?\?\s*\[\]\)/input.setStore("agent", Array.isArray(x.data) ? x.data : [])/g' \
   "${BOOTSTRAP_TS}"
-echo "[opencode-embed] Patched bootstrap.ts: Array.isArray guard on agent store"
+if grep -q 'Array\.isArray(x\.data)' "${BOOTSTRAP_TS}"; then
+  echo "[opencode-embed] Patched bootstrap.ts: Array.isArray guard on agent store"
+else
+  echo "[opencode-embed] ERROR: bootstrap.ts patch did not apply — upstream may have changed."
+  exit 1
+fi

🤖 Prompt for AI Agents

Verify each finding against the current code and only fix it if needed.

In `@scripts/build-opencode-embed.sh` around lines 114 - 125, The current perl
substitutions for the patterns containing "sync.data.agent.filter" and
'input.setStore("agent", x.data ?? [])' may be no-ops if upstream changed those
lines; after each patch command (targeting sync.data.agent.filter and
input.setStore("agent", x.data ?? [])), add a verification step that checks the
file for the new guarded form (Array.isArray(...)) and fail the script if the
expected replacement wasn't applied so the CI/build stops (e.g., grep for
"Array.isArray(sync.data.agent" and 'input.setStore("agent",
Array.isArray(x.data)' or count replacements and exit non-zero when zero),
ensuring you reference the exact symbols "sync.data.agent.filter" and
'input.setStore("agent", x.data ?? [])' to locate the original lines and the
guarded forms to verify.

🤖 Prompt for all review comments with AI agents

Verify each finding against the current code and only fix it if needed.

Nitpick comments:
In `@scripts/build-opencode-embed.sh`:
- Around line 114-125: The current perl substitutions for the patterns
containing "sync.data.agent.filter" and 'input.setStore("agent", x.data ?? [])'
may be no-ops if upstream changed those lines; after each patch command
(targeting sync.data.agent.filter and input.setStore("agent", x.data ?? [])),
add a verification step that checks the file for the new guarded form
(Array.isArray(...)) and fail the script if the expected replacement wasn't
applied so the CI/build stops (e.g., grep for "Array.isArray(sync.data.agent"
and 'input.setStore("agent", Array.isArray(x.data)' or count replacements and
exit non-zero when zero), ensuring you reference the exact symbols
"sync.data.agent.filter" and 'input.setStore("agent", x.data ?? [])' to locate
the original lines and the guarded forms to verify.

---

ℹ️ Review info

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: acf2a670-5b40-4698-9dd5-c95a711dd2f7

📥 Commits

Reviewing files that changed from the base of the PR and between 6f81f39 and b8a6bdd.

📒 Files selected for processing (1)

• scripts/build-opencode-embed.sh