DateGuard -- Date/Time Anti-Pattern Scanner
DateGuard scans codebases for date/time anti-patterns, timezone bugs, naive datetime usage, hardcoded timestamps, non-ISO formats, incorrect epoch handling, DST-unsafe comparisons, locale-dependent parsing, and temporal storage issues. It uses regex-based pattern matching against 90 date/time-specific patterns across 6 categories, lefthook for git hook integration, and produces markdown reports with actionable remediation guidance. 100% local. Zero telemetry.
Commands
Free Tier (No license required)
dateguard scan [file|directory]
One-shot date/time quality scan of files or directories.
How to execute:
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [target]
What it does:
- Accepts a file path or directory (defaults to current directory)
- Discovers all source files (skips .git, node_modules, binaries, images, .min.js)
- Runs 30 date/time quality patterns against each file (free tier limit)
- Calculates a date/time quality score (0-100) per file and overall
- Grades: A (90-100), B (80-89), C (70-79), D (60-69), F (<60)
- Outputs findings with: file, line number, check ID, severity, description, recommendation
- Exit code 0 if score >= 70, exit code 1 if date/time quality is poor
- Free tier limited to first 30 patterns (TZ + NF categories)
Example usage scenarios:
- "Scan my code for timezone issues" -> runs
dateguard scan .
- "Check this file for date anti-patterns" -> runs
dateguard scan src/server.ts
- "Find naive datetime usage" -> runs
dateguard scan src/
- "Audit date/time handling in my project" -> runs
dateguard scan .
- "Check for DST-unsafe date math" -> runs
dateguard scan .
Pro Tier ($19/user/month -- requires DATEGUARD_LICENSE_KEY)
dateguard scan --tier pro [file|directory]
Extended scan with 60 patterns covering timezone, formatting, epoch precision, and date arithmetic.
How to execute:
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [target] --tier pro
What it does:
- Validates Pro+ license
- Runs 60 date/time patterns (TZ, NF, EP, DA categories)
- Detects epoch precision bugs (ms vs seconds confusion)
- Identifies DST-unsafe date arithmetic
- Full category breakdown reporting
dateguard scan --format json [directory]
Generate JSON output for CI/CD integration.
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --format json
dateguard scan --format html [directory]
Generate HTML report for browser viewing.
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --format html
dateguard scan --category EP [directory]
Filter scan to a specific check category (TZ, NF, EP, DA, CP, ST).
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --category EP
Team Tier ($39/user/month -- requires DATEGUARD_LICENSE_KEY with team tier)
dateguard scan --tier team [directory]
Full scan with all 90 patterns across all 6 categories including comparison/parsing and storage/serialization.
How to execute:
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --tier team
What it does:
- Validates Team+ license
- Runs all 90 patterns across 6 categories
- Includes comparison/parsing checks (string date comparison, == on Date objects)
- Includes storage/serialization checks (VARCHAR for dates, missing timezone in DB)
- Full category breakdown with per-file results
dateguard scan --verbose [directory]
Verbose output showing every matched line and pattern details.
bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --verbose
dateguard status
Show license and configuration information.
bash "<SKILL_DIR>/scripts/dispatcher.sh" status
Check Categories
DateGuard detects 90 date/time anti-patterns across 6 categories:
| Category |
Code |
Patterns |
Description |
Severity Range |
| Timezone Handling |
TZ |
15 |
Missing timezone in datetime creation, implicit local timezone, hardcoded offsets, timezone conversion without DST handling |
medium -- high |
| Naive Formatting |
NF |
15 |
Non-ISO date formats in APIs, locale-dependent parsing, ambiguous MM/DD vs DD/MM, toString() on dates |
low -- high |
| Epoch & Precision |
EP |
15 |
Millisecond vs second confusion, Y2038 risk, timestamps as strings, floating point timestamps, epoch 0 sentinels |
low -- medium |
| Date Arithmetic |
DA |
15 |
Manual +86400 day math, month arithmetic ignoring varying lengths, leap year bugs, DST-crossing calculations |
medium -- high |
| Comparison & Parsing |
CP |
15 |
Lexicographic date string comparison, Date == comparison, unparsed user input, timezone-unaware comparisons |
medium -- high |
| Storage & Serialization |
ST |
15 |
VARCHAR for timestamps in SQL, missing timezone in stored dates, JSON.stringify on Date, hardcoded date strings |
low -- high |
Tier-Based Pattern Access
| Tier |
Patterns |
Categories |
| Free |
30 |
TZ, NF |
| Pro |
60 |
TZ, NF, EP, DA |
| Team |
90 |
TZ, NF, EP, DA, CP, ST |
| Enterprise |
90 |
TZ, NF, EP, DA, CP, ST + priority support |
Scoring
DateGuard uses a deductive scoring system starting at 100 (perfect):
| Severity |
Point Deduction |
Description |
| Critical |
-25 per finding |
Severe temporal bug (Y2038, data loss from timezone) |
| High |
-15 per finding |
Significant quality problem (naive datetime, DST math) |
| Medium |
-8 per finding |
Moderate concern (ambiguous formats, missing timezone) |
| Low |
-3 per finding |
Informational / best practice suggestion |
Grading Scale
| Grade |
Score Range |
Meaning |
| A |
90-100 |
Excellent date/time handling |
| B |
80-89 |
Good handling with minor issues |
| C |
70-79 |
Acceptable but needs improvement |
| D |
60-69 |
Poor date/time quality |
| F |
Below 60 |
Critical temporal problems |
- Pass threshold: 70 (Grade C or better)
- Exit code 0 = pass (score >= 70)
- Exit code 1 = fail (score < 70)
Configuration
Users can configure DateGuard in ~/.openclaw/openclaw.json:
{
"skills": {
"entries": {
"dateguard": {
"enabled": true,
"apiKey": "YOUR_LICENSE_KEY_HERE",
"config": {
"severityThreshold": "medium",
"ignorePatterns": ["**/test/**", "**/fixtures/**", "**/*.test.*"],
"ignoreChecks": [],
"reportFormat": "text"
}
}
}
}
}
Important Notes
- Free tier works immediately with no configuration
- All scanning happens locally -- no code is sent to external servers
- License validation is offline -- no phone-home or network calls
- Pattern matching only -- no AST parsing, no external dependencies beyond bash
- Supports scanning all file types in a single pass
- Git hooks use lefthook which must be installed (see install metadata above)
- Exit codes: 0 = pass (score >= 70), 1 = fail (for CI/CD integration)
- Output formats: text (default), json, html
Error Handling
- If lefthook is not installed and user tries hooks, prompt to install it
- If license key is invalid or expired, show clear message with link to https://dateguard.pages.dev/renew
- If a file is binary, skip it automatically with no warning
- If no scannable files found in target, report clean scan with info message
- If an invalid category is specified with --category, show available categories
When to Use DateGuard
The user might say things like:
- "Scan my code for timezone issues"
- "Check my date/time handling"
- "Find naive datetime usage"
- "Detect DST-unsafe date math"
- "Are there any hardcoded timestamps?"
- "Check for missing timezone handling"
- "Audit my date/time practices"
- "Find ambiguous date formats"
- "Check for epoch precision bugs"
- "Scan for date/time anti-patterns"
- "Run a date/time quality audit"
- "Generate a date/time quality report"
- "Check if dates are stored properly in my database schema"
- "Find Date objects compared with == instead of getTime()"
- "Check my code for Y2038 risks"
1---2name: dateguard-23description: Date/time anti-pattern scanner -- detects timezone bugs, naive datetime usage, hardcoded timestamps, non-ISO formats, incorrect epoch handling, DST-unsafe comparisons, and temporal anti-patterns4---56# DateGuard -- Date/Time Anti-Pattern Scanner78DateGuard scans codebases for date/time anti-patterns, timezone bugs, naive datetime usage, hardcoded timestamps, non-ISO formats, incorrect epoch handling, DST-unsafe comparisons, locale-dependent parsing, and temporal storage issues. It uses regex-based pattern matching against 90 date/time-specific patterns across 6 categories, lefthook for git hook integration, and produces markdown reports with actionable remediation guidance. 100% local. Zero telemetry.910## Commands1112### Free Tier (No license required)1314#### `dateguard scan [file|directory]`15One-shot date/time quality scan of files or directories.1617**How to execute:**18```bash19bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [target]20```2122**What it does:**231. Accepts a file path or directory (defaults to current directory)242. Discovers all source files (skips .git, node_modules, binaries, images, .min.js)253. Runs 30 date/time quality patterns against each file (free tier limit)264. Calculates a date/time quality score (0-100) per file and overall275. Grades: A (90-100), B (80-89), C (70-79), D (60-69), F (<60)286. Outputs findings with: file, line number, check ID, severity, description, recommendation297. Exit code 0 if score >= 70, exit code 1 if date/time quality is poor308. Free tier limited to first 30 patterns (TZ + NF categories)3132**Example usage scenarios:**33- "Scan my code for timezone issues" -> runs `dateguard scan .`34- "Check this file for date anti-patterns" -> runs `dateguard scan src/server.ts`35- "Find naive datetime usage" -> runs `dateguard scan src/`36- "Audit date/time handling in my project" -> runs `dateguard scan .`37- "Check for DST-unsafe date math" -> runs `dateguard scan .`3839### Pro Tier ($19/user/month -- requires DATEGUARD_LICENSE_KEY)4041#### `dateguard scan --tier pro [file|directory]`42Extended scan with 60 patterns covering timezone, formatting, epoch precision, and date arithmetic.4344**How to execute:**45```bash46bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [target] --tier pro47```4849**What it does:**501. Validates Pro+ license512. Runs 60 date/time patterns (TZ, NF, EP, DA categories)523. Detects epoch precision bugs (ms vs seconds confusion)534. Identifies DST-unsafe date arithmetic545. Full category breakdown reporting5556#### `dateguard scan --format json [directory]`57Generate JSON output for CI/CD integration.5859```bash60bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --format json61```6263#### `dateguard scan --format html [directory]`64Generate HTML report for browser viewing.6566```bash67bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --format html68```6970#### `dateguard scan --category EP [directory]`71Filter scan to a specific check category (TZ, NF, EP, DA, CP, ST).7273```bash74bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --category EP75```7677### Team Tier ($39/user/month -- requires DATEGUARD_LICENSE_KEY with team tier)7879#### `dateguard scan --tier team [directory]`80Full scan with all 90 patterns across all 6 categories including comparison/parsing and storage/serialization.8182**How to execute:**83```bash84bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --tier team85```8687**What it does:**881. Validates Team+ license892. Runs all 90 patterns across 6 categories903. Includes comparison/parsing checks (string date comparison, == on Date objects)914. Includes storage/serialization checks (VARCHAR for dates, missing timezone in DB)925. Full category breakdown with per-file results9394#### `dateguard scan --verbose [directory]`95Verbose output showing every matched line and pattern details.9697```bash98bash "<SKILL_DIR>/scripts/dispatcher.sh" --path [directory] --verbose99```100101#### `dateguard status`102Show license and configuration information.103104```bash105bash "<SKILL_DIR>/scripts/dispatcher.sh" status106```107108## Check Categories109110DateGuard detects 90 date/time anti-patterns across 6 categories:111112| Category | Code | Patterns | Description | Severity Range |113|----------|------|----------|-------------|----------------|114| **Timezone Handling** | TZ | 15 | Missing timezone in datetime creation, implicit local timezone, hardcoded offsets, timezone conversion without DST handling | medium -- high |115| **Naive Formatting** | NF | 15 | Non-ISO date formats in APIs, locale-dependent parsing, ambiguous MM/DD vs DD/MM, toString() on dates | low -- high |116| **Epoch & Precision** | EP | 15 | Millisecond vs second confusion, Y2038 risk, timestamps as strings, floating point timestamps, epoch 0 sentinels | low -- medium |117| **Date Arithmetic** | DA | 15 | Manual +86400 day math, month arithmetic ignoring varying lengths, leap year bugs, DST-crossing calculations | medium -- high |118| **Comparison & Parsing** | CP | 15 | Lexicographic date string comparison, Date == comparison, unparsed user input, timezone-unaware comparisons | medium -- high |119| **Storage & Serialization** | ST | 15 | VARCHAR for timestamps in SQL, missing timezone in stored dates, JSON.stringify on Date, hardcoded date strings | low -- high |120121## Tier-Based Pattern Access122123| Tier | Patterns | Categories |124|------|----------|------------|125| **Free** | 30 | TZ, NF |126| **Pro** | 60 | TZ, NF, EP, DA |127| **Team** | 90 | TZ, NF, EP, DA, CP, ST |128| **Enterprise** | 90 | TZ, NF, EP, DA, CP, ST + priority support |129130## Scoring131132DateGuard uses a deductive scoring system starting at 100 (perfect):133134| Severity | Point Deduction | Description |135|----------|-----------------|-------------|136| **Critical** | -25 per finding | Severe temporal bug (Y2038, data loss from timezone) |137| **High** | -15 per finding | Significant quality problem (naive datetime, DST math) |138| **Medium** | -8 per finding | Moderate concern (ambiguous formats, missing timezone) |139| **Low** | -3 per finding | Informational / best practice suggestion |140141### Grading Scale142143| Grade | Score Range | Meaning |144|-------|-------------|---------|145| **A** | 90-100 | Excellent date/time handling |146| **B** | 80-89 | Good handling with minor issues |147| **C** | 70-79 | Acceptable but needs improvement |148| **D** | 60-69 | Poor date/time quality |149| **F** | Below 60 | Critical temporal problems |150151- **Pass threshold:** 70 (Grade C or better)152- Exit code 0 = pass (score >= 70)153- Exit code 1 = fail (score < 70)154155## Configuration156157Users can configure DateGuard in `~/.openclaw/openclaw.json`:158159```json160{161 "skills": {162 "entries": {163 "dateguard": {164 "enabled": true,165 "apiKey": "YOUR_LICENSE_KEY_HERE",166 "config": {167 "severityThreshold": "medium",168 "ignorePatterns": ["**/test/**", "**/fixtures/**", "**/*.test.*"],169 "ignoreChecks": [],170 "reportFormat": "text"171 }172 }173 }174 }175}176```177178## Important Notes179180- **Free tier** works immediately with no configuration181- **All scanning happens locally** -- no code is sent to external servers182- **License validation is offline** -- no phone-home or network calls183- Pattern matching only -- no AST parsing, no external dependencies beyond bash184- Supports scanning all file types in a single pass185- Git hooks use **lefthook** which must be installed (see install metadata above)186- Exit codes: 0 = pass (score >= 70), 1 = fail (for CI/CD integration)187- Output formats: text (default), json, html188189## Error Handling190191- If lefthook is not installed and user tries hooks, prompt to install it192- If license key is invalid or expired, show clear message with link to https://dateguard.pages.dev/renew193- If a file is binary, skip it automatically with no warning194- If no scannable files found in target, report clean scan with info message195- If an invalid category is specified with --category, show available categories196197## When to Use DateGuard198199The user might say things like:200- "Scan my code for timezone issues"201- "Check my date/time handling"202- "Find naive datetime usage"203- "Detect DST-unsafe date math"204- "Are there any hardcoded timestamps?"205- "Check for missing timezone handling"206- "Audit my date/time practices"207- "Find ambiguous date formats"208- "Check for epoch precision bugs"209- "Scan for date/time anti-patterns"210- "Run a date/time quality audit"211- "Generate a date/time quality report"212- "Check if dates are stored properly in my database schema"213- "Find Date objects compared with == instead of getTime()"214- "Check my code for Y2038 risks"