[nightshift] error-msg-improve: error message quality analysis

[nightshift-micr]

Error Message Quality Report

Repository: Microck/tailstick
Task: error-msg-improve
Date: 2026-04-20

Summary

Severity	Count	Description
P0	5	User-blocking or security-relevant silent failures
P1	8	Missing error context, debugging-blind spots
P2	14	Bare return err without operation context
P3	4	Quality improvements / nice-to-have

Total findings: 31 (41 bare return err, 21 ignored errors, 12 fmt.Errorf without %w, 5 silent failures)

P0 — Security / User-Blocking

1. client.go:148 — DeleteDevice returns nil (success) when apiKey/deviceID is empty. Silently skips device deletion, leaving orphaned devices.
2. workflow.go:334 — json.Unmarshal failure silently ignored during cleanup decryption. Wrong cleanup config = skipped device deletion.
3. server.go:174 — GUI enroll endpoint returns HTTP 400 for all errors including server-side failures. Leaks internal error messages (file paths, encryption details) to browser.
4. workflow.go:370 — Audit write failure silently swallowed during cleanup (_ = state.AppendAudit(...)). Loses audit trail.
5. cli.go:60,115,157 — Flag parse errors exit code 2 with no message. User sees silent exit.

P1 — Debugging-Critical

1. crypto/secret.go — Encrypt has 7 bare errors with zero context. Decrypt has 10. Impossible to diagnose which step failed.
2. workflow.go:48-70 — NewManager returns 4 bare errors without context.
3. workflow.go:718-740 — resolveCleanupFromConfig/resolvePresetFromConfig silently swallow errors and return empty config.
4. workflow.go:98-190 — Enroll returns 8 bare errors. User only sees "enroll: ".
5. client.go:89-105 — Tailscale Up/Down/Logout/Status return bare runner errors.
6. client.go:108-115 — Status JSON parse failure silently falls through to fallback.
7. client.go:152-158 — DeleteDevice HTTP errors returned without context.

P2 — Quality (41 bare return err)

Key files: workflow.go (18 occurrences), tailscale/client.go (6), state/store.go (6), platform/platform.go (1), logging/logger.go (2).

Most impactful: crypto/secret.go — 18 bare error returns make debugging cryptographic failures impossible.
Most impactful pattern: workflow.go Enroll method — 8 sequential operations all return bare errors.

Recommended Fixes

Immediate (P0)

• Return errors instead of nil for empty DeleteDevice inputs
• Handle json.Unmarshal errors during cleanup
• Distinguish user errors (400) from server errors (500) in GUI
• Log audit write failures
• Print flag parse errors + usage on exit

Short-term (P1)

• Wrap ALL errors in crypto/secret.go with fmt.Errorf("step: %w", err)
• Wrap NewManager, Enroll errors with operation context
• Change resolveCleanupFromConfig to return errors instead of empty config

Medium-term (P2)

• Systematically wrap all bare return err with fmt.Errorf("operation: %w", err)
• Ensure all fmt.Errorf use %w for error chain preservation

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Automated by Nightshift v3 (GLM 5.1)

[Microck]

Resolved via #43 for the actionable items (GUI error-surface hardening and clearer validation errors). Closing this generated audit report as superseded by current main.