Config parse error is silently swallowed: entire magic-context.jsonc falls back to defaults with only a log-file warning

[G0-0000]

What happened?

A single-character syntax error in magic-context.jsonc silently disables the entire config file — every customized option falls back to schema defaults with no error surfaced to the user.

Repro:

1. Introduce any JSONC syntax error into ~/.config/cortexkit/magic-context.jsonc — in our real incident, the first line was accidentally written as \{ instead of { (one stray backslash).
2. Start a Pi session. The plugin loads normally; no error is shown anywhere in the UI.
3. Observe that ALL config customizations are now inert: cache_ttl reverts to "5m", custom dreamer schedules, model routing, thresholds, etc. all silently revert to schema defaults.

Root cause (0.41.2): loadConfigFile wraps comment-json parsing in a try/catch; on parse failure it returns config: {} plus a warning string "failed to load config: ...; using defaults for this file." (Pi bundle dist/index-ys39wb43.js L40295-40330; CLI bundle dist/index.js L43242-43280). The Zod schema then fills every field with its default (e.g. cache_ttl union has .default("5m"), CLI bundle L37669). The warning is only emitted via logPiConfigLoad → warn() (dist/index.js L30525-30539), which writes to the magic-context log file (/tmp/magic-context.log) — it is never surfaced as a UI notification, so from the user's perspective everything looks normal while the whole config is dead.

In our incident (2026-09-02) this went unnoticed and misdirected debugging: /ctx-status showed Cache TTL: 5m despite "cache_ttl": "1h" in the file, and we spent time checking env vars, version drift, and backup diffs before finding the single stray \ on line 1. A more forgiving parser (jsonc-parser) skips the bad first character and still reads the rest of the file — the rest of the config was perfectly valid; one character killed everything.

Expected:

• Parse errors should be fail-loud: surface a UI warning/notification at session start ("config file failed to parse — running on defaults"), and/or
• /ctx-status (or doctor) should prominently report "config parse failed, using defaults" as a health state, and/or
• Optionally: attempt tolerant parsing (e.g. jsonc-parser's error-recovery) and apply the recoverable subset instead of discarding the entire file.

A single typo silently reverting the whole configuration is a sharp edge: the failure mode is indistinguishable from "config ignored", which is the hardest class of config bug to diagnose.

Diagnostics

doctor --issue unavailable: `npx @cortexkit/magic-context@latest doctor --issue --harness pi` launched an interactive TUI (prompted for Issue title: "Short summary of the Pi problem") instead of dumping diagnostics to stdout or a report file; exit 0, no issue-report file produced.

Non-interactive `npx @cortexkit/magic-context@latest doctor --harness pi` output (2026-09-08):

Running doctor for Pi…
Magic Context for Pi Doctor
PASS Pi 0.84.4 detected at /home/g0/.local/bin/pi
PASS Pi version meets minimum 0.74.0 requirement
PASS Magic Context Pi CLI v0.41.2 is current (npm latest v0.41.2)
PASS Pi settings found at /home/g0/.pi/agent/settings.json
PASS npm:@cortexkit/pi-magic-context is registered in packages[]
PASS user magic-context.jsonc is valid JSONC: /home/g0/.config/cortexkit/magic-context.jsonc
INFO No project Magic Context config found at /home/g0/ttt/.cortexkit/magic-context.jsonc
PASS Pi Magic Context config loads successfully
INFO Shared storage: /home/g0/.local/share/cortexkit/magic-context (source: platform default)
PASS Shared context DB exists at /home/g0/.local/share/cortexkit/magic-context/context.db
PASS Opened shared DB read-only supported schema
INFO Storage versions: context_db_schema_version=83, plugin_supported_version=83
INFO Upstream migration fence: context.db and build are both v83.
PASS SQLite integrity_check: ok
INFO Shared DB row counts: tags=64144, compartments=85, memories=308, notes=14, dream_runs=335
PASS Embedding endpoint OK (200, 2560-dim vectors)
PASS No conflicting magic-context entries in Pi packages[]
INFO Other Pi extensions registered: npm:pi-subagents, git:github.com/Leechael/pi-provider-kimi-code, npm:@ff-labs/pi-fff, npm:@victor-software-house/pi-curated-themes, npm:pi-open-tui, npm:pi-mcp-adapter, npm:pi-rtk-optimizer, npm:@juicesharp/rpiv-ask-user-question, npm:@tmustier/pi-usage-extension, npm:pi-cache-guardian
INFO log: /tmp/pi/magic-context/magic-context.log (3887 KB)
INFO [2026-09-04T17:53:05.266Z] projects=1
PASS 13  WARN 0  FAIL 0

Plugin version: 0.41.2

OpenCode version: N/A

Platform: linux x64

Client: Pi

Log output (optional)

[magic-context] WARN config: /home/…/magic-context.jsonc: failed to load config: Line 1: Unexpected token ILLEGAL; using defaults for this file.

[magic-alfonso]

Thanks for the precise report. Your 0.41.2 source cites were exact: the runtime row still starts from cacheTtl: "5m", is inserted with INSERT OR IGNORE, and maps an empty database value back to "5m" (packages/plugin/src/features/magic-context/storage-meta-shared.ts:307-316, :365-389, :408-416). The config loader also did reduce a whole-file comment-json exception to {} plus a warning that Pi only logged.

This is fixed on master and ships in 0.41.4 (0.41.3 was already cut when this landed) without disabling the plugin:

• OpenCode and Pi now use the existing jsonc-parser dependency in recovery mode. Your exact \\{ first-line case recovers the remaining object, so the valid settings are applied, but recovery is still classified as a file parse failure rather than a clean load (packages/plugin/src/config/index.ts:153-205).
• Parse failures carry the file path, line, column, parser message, and recovered/default disposition. They are a different warning class from invalid leaf values.
• The existing prototype-pollution boundary remains in place. Recovered objects are normalized and __proto__, constructor, and prototype keys are rejected before merge (packages/plugin/src/shared/jsonc-parser.ts:125-157, :160-205).
• OpenCode routes the failure through the ## ⚠️ Magic Context Config Warning banner at top severity and claims each parse notice once per process (packages/plugin/src/index.ts:145-201). Pi emits an error-level session-start UI notification through ctx.ui.notify, also once per process (packages/pi-plugin/src/index.ts:1337-1362).
• /ctx-status, the OpenCode status dialog, and the Pi status dialog put Config: PARSE FAILED (<path>:<line>:<column>) first. The dashboard config editor switches to Raw JSONC and shows the same failure instead of rendering an apparently configured defaults form.

On the doctor PASS discrepancy: 0.41.2's Pi doctor and Pi runtime both used comment-json; there was not a second parser that accepted the leading backslash. The diagnostic shown in the report was captured on 2026-09-08, after the 2026-09-02 incident/file repair, so it could legitimately PASS then. On master (0.41.4) doctor calls the same recovering parser as the runtime and treats any recovery diagnostic as invalid, so a recovered \\{ file is a FAIL, not a PASS (packages/cli/src/commands/doctor-pi.ts:264-297).

The side finding is fixed too: doctor --issue --harness pi --report <path> writes the sanitized bundle directly without opening the interactive title/description flow (packages/cli/src/commands/doctor-pi.ts:1049-1073).

[ualtinok]

Fixed in v0.41.4: an unparseable magic-context.jsonc is now loud on every surface instead of silently falling back to defaults — OpenCode banner, Pi/OMP session notice, the first line of /ctx-status, the dashboard, and doctor (which also gained doctor --report <path> for a specific file). Closing.