Track construction retainage/retention amounts. Monitor held amounts by subcontractor, track release conditions, and manage retainage billing.
npx skills add https://github.com/datadrivenconstruction/DDC_Skills_for_AI_Agents_in_Construction --skill retention-tracker
Track retainage (retention) amounts held and released throughout construction projects. Monitor amounts by subcontractor, track release milestones, and ensure proper documentation for retention release.
┌─────────────────────────────────────────────────────────────────┐
│ RETAINAGE LIFECYCLE │
├─────────────────────────────────────────────────────────────────┤
│ │
│ Progress Billing → Substantial → Final Release │
│ ──────────────── ─────────── ───────────── │
│ 10% withheld 50% released 50% released │
│ Each pay app At punch list At final │
│ Cumulative completion completion │
│ │
│ Owner holds from GC → GC holds from subs → Flow-down │
│ │
└─────────────────────────────────────────────────────────────────┘
from dataclasses import dataclass, field
from typing import List, Dict, Optional
from datetime import datetime, timedelta
from enum import Enum
class RetentionStatus(Enum):
HELD = "held"
PARTIAL_RELEASE = "partial_release"
PENDING_RELEASE = "pending_release"
RELEASED = "released"
class ReleaseMilestone(Enum):
SUBSTANTIAL_COMPLETION = "substantial_completion"
PUNCH_LIST_COMPLETE = "punch_list_complete"
FINAL_COMPLETION = "final_completion"
WARRANTY_EXPIRATION = "warranty_expiration"
@dataclass
class RetentionEntry:
pay_app_number: int
billing_date: datetime
gross_billing: float
retention_rate: float
retention_amount: float
status: RetentionStatus = RetentionStatus.HELD
@dataclass
class RetentionRelease:
id: str
release_date: datetime
milestone: ReleaseMilestone
amount: float
remaining_after: float
approved_by: str
conditions_met: List[str] = field(default_factory=list)
lien_waivers_received: bool = False
consent_of_surety: bool = False
@dataclass
class SubcontractorRetention:
subcontractor_id: str
subcontractor_name: str
trade: str
contract_value: float
retention_rate: float
entries: List[RetentionEntry] = field(default_factory=list)
releases: List[RetentionRelease] = field(default_factory=list)
total_billed: float = 0.0
total_retained: float = 0.0
total_released: float = 0.0
balance_held: float = 0.0
status: RetentionStatus = RetentionStatus.HELD
class RetentionTracker:
"""Track construction retainage amounts."""
# Default release schedule
DEFAULT_RELEASE_SCHEDULE = {
ReleaseMilestone.SUBSTANTIAL_COMPLETION: 0.50, # 50% at substantial
ReleaseMilestone.FINAL_COMPLETION: 0.50, # 50% at final
}
def __init__(self, project_name: str, default_rate: float = 0.10):
self.project_name = project_name
self.default_rate = default_rate
self.subcontractors: Dict[str, SubcontractorRetention] = {}
self.release_schedule = dict(self.DEFAULT_RELEASE_SCHEDULE)
# Project-level retention (from owner)
self.owner_retention = SubcontractorRetention(
subcontractor_id="OWNER",
subcontractor_name="Owner Retention",
trade="GC",
contract_value=0,
retention_rate=default_rate
)
def set_release_schedule(self, schedule: Dict[ReleaseMilestone, float]):
"""Set custom release schedule."""
self.release_schedule = schedule
def add_subcontractor(self, id: str, name: str, trade: str,
contract_value: float,
retention_rate: float = None) -> SubcontractorRetention:
"""Add subcontractor to track."""
sub = SubcontractorRetention(
subcontractor_id=id,
subcontractor_name=name,
trade=trade,
contract_value=contract_value,
retention_rate=retention_rate if retention_rate else self.default_rate
)
self.subcontractors[id] = sub
return sub
def record_billing(self, subcontractor_id: str, pay_app_number: int,
billing_date: datetime, gross_billing: float) -> RetentionEntry:
"""Record billing and calculate retention."""
if subcontractor_id not in self.subcontractors:
raise ValueError(f"Subcontractor {subcontractor_id} not found")
sub = self.subcontractors[subcontractor_id]
retention_amount = gross_billing * sub.retention_rate
entry = RetentionEntry(
pay_app_number=pay_app_number,
billing_date=billing_date,
gross_billing=gross_billing,
retention_rate=sub.retention_rate,
retention_amount=retention_amount
)
sub.entries.append(entry)
# Update totals
sub.total_billed += gross_billing
sub.total_retained += retention_amount
sub.balance_held = sub.total_retained - sub.total_released
return entry
def record_owner_billing(self, pay_app_number: int, billing_date: datetime,
gross_billing: float) -> RetentionEntry:
"""Record owner-level retention."""
retention_amount = gross_billing * self.owner_retention.retention_rate
entry = RetentionEntry(
pay_app_number=pay_app_number,
billing_date=billing_date,
gross_billing=gross_billing,
retention_rate=self.owner_retention.retention_rate,
retention_amount=retention_amount
)
self.owner_retention.entries.append(entry)
self.owner_retention.total_billed += gross_billing
self.owner_retention.total_retained += retention_amount
self.owner_retention.balance_held = (
self.owner_retention.total_retained - self.owner_retention.total_released
)
return entry
def release_retention(self, subcontractor_id: str, milestone: ReleaseMilestone,
amount: float = None, approved_by: str = "",
conditions: List[str] = None,
lien_waivers: bool = False,
consent_of_surety: bool = False) -> RetentionRelease:
"""Release retention for subcontractor."""
if subcontractor_id not in self.subcontractors:
raise ValueError(f"Subcontractor {subcontractor_id} not found")
sub = self.subcontractors[subcontractor_id]
# Calculate release amount if not specified
if amount is None:
release_pct = self.release_schedule.get(milestone, 0.5)
amount = sub.balance_held * release_pct
if amount > sub.balance_held:
amount = sub.balance_held
release_id = f"REL-{subcontractor_id}-{len(sub.releases)+1:03d}"
release = RetentionRelease(
id=release_id,
release_date=datetime.now(),
milestone=milestone,
amount=amount,
remaining_after=sub.balance_held - amount,
approved_by=approved_by,
conditions_met=conditions or [],
lien_waivers_received=lien_waivers,
consent_of_surety=consent_of_surety
)
sub.releases.append(release)
sub.total_released += amount
sub.balance_held -= amount
if sub.balance_held <= 0:
sub.status = RetentionStatus.RELEASED
elif sub.total_released > 0:
sub.status = RetentionStatus.PARTIAL_RELEASE
return release
def release_owner_retention(self, milestone: ReleaseMilestone,
amount: float = None,
approved_by: str = "") -> RetentionRelease:
"""Release owner-level retention."""
if amount is None:
release_pct = self.release_schedule.get(milestone, 0.5)
amount = self.owner_retention.balance_held * release_pct
if amount > self.owner_retention.balance_held:
amount = self.owner_retention.balance_held
release_id = f"REL-OWNER-{len(self.owner_retention.releases)+1:03d}"
release = RetentionRelease(
id=release_id,
release_date=datetime.now(),
milestone=milestone,
amount=amount,
remaining_after=self.owner_retention.balance_held - amount,
approved_by=approved_by
)
self.owner_retention.releases.append(release)
self.owner_retention.total_released += amount
self.owner_retention.balance_held -= amount
return release
def check_release_conditions(self, subcontractor_id: str) -> Dict:
"""Check conditions required for retention release."""
if subcontractor_id not in self.subcontractors:
raise ValueError(f"Subcontractor {subcontractor_id} not found")
sub = self.subcontractors[subcontractor_id]
conditions = {
"punch_list_complete": False, # Check externally
"final_lien_waiver": False,
"consent_of_surety": False,
"as_builts_submitted": False,
"warranty_documents": False,
"training_complete": False,
"closeout_docs": False
}
# Check last release for received items
if sub.releases:
last_release = sub.releases[-1]
conditions["final_lien_waiver"] = last_release.lien_waivers_received
conditions["consent_of_surety"] = last_release.consent_of_surety
missing = [k for k, v in conditions.items() if not v]
return {
"subcontractor": sub.subcontractor_name,
"balance_held": sub.balance_held,
"conditions_status": conditions,
"missing_conditions": missing,
"ready_for_release": len(missing) == 0
}
def get_retention_summary(self) -> Dict:
"""Get overall retention summary."""
total_retained = sum(s.total_retained for s in self.subcontractors.values())
total_released = sum(s.total_released for s in self.subcontractors.values())
total_held = sum(s.balance_held for s in self.subcontractors.values())
by_status = {}
for sub in self.subcontractors.values():
status = sub.status.value
by_status[status] = by_status.get(status, 0) + 1
return {
"owner_retained": self.owner_retention.total_retained,
"owner_released": self.owner_retention.total_released,
"owner_balance": self.owner_retention.balance_held,
"sub_total_retained": total_retained,
"sub_total_released": total_released,
"sub_balance_held": total_held,
"net_retention_position": self.owner_retention.balance_held - total_held,
"subcontractors_count": len(self.subcontractors),
"by_status": by_status
}
def get_aged_retention(self) -> List[Dict]:
"""Get aged retention report."""
aged = []
for sub in self.subcontractors.values():
if sub.balance_held <= 0:
continue
# Find oldest unreleased entry
oldest_date = None
for entry in sub.entries:
if entry.status == RetentionStatus.HELD:
if oldest_date is None or entry.billing_date < oldest_date:
oldest_date = entry.billing_date
days_held = (datetime.now() - oldest_date).days if oldest_date else 0
aged.append({
"subcontractor_id": sub.subcontractor_id,
"subcontractor_name": sub.subcontractor_name,
"trade": sub.trade,
"balance_held": sub.balance_held,
"oldest_entry_date": oldest_date,
"days_held": days_held
})
return sorted(aged, key=lambda x: -x["days_held"])
def forecast_releases(self, substantial_date: datetime,
final_date: datetime) -> List[Dict]:
"""Forecast retention releases."""
forecasts = []
for sub in self.subcontractors.values():
if sub.balance_held <= 0:
continue
# Substantial completion release
sub_release = sub.balance_held * self.release_schedule.get(
ReleaseMilestone.SUBSTANTIAL_COMPLETION, 0.5
)
forecasts.append({
"date": substantial_date,
"subcontractor": sub.subcontractor_name,
"milestone": "Substantial Completion",
"amount": sub_release
})
# Final completion release
final_release = sub.balance_held - sub_release
forecasts.append({
"date": final_date,
"subcontractor": sub.subcontractor_name,
"milestone": "Final Completion",
"amount": final_release
})
return sorted(forecasts, key=lambda x: x["date"])
def generate_report(self) -> str:
"""Generate retention status report."""
summary = self.get_retention_summary()
lines = [
"# Retention Status Report",
"",
f"**Project:** {self.project_name}",
f"**Date:** {datetime.now().strftime('%Y-%m-%d')}",
"",
"## Summary",
"",
"### Owner Retention",
"",
f"| Metric | Amount |",
f"|--------|--------|",
f"| Total Retained | ${summary['owner_retained']:,.0f} |",
f"| Total Released | ${summary['owner_released']:,.0f} |",
f"| **Balance Held** | **${summary['owner_balance']:,.0f}** |",
"",
"### Subcontractor Retention",
"",
f"| Metric | Amount |",
f"|--------|--------|",
f"| Total Retained | ${summary['sub_total_retained']:,.0f} |",
f"| Total Released | ${summary['sub_total_released']:,.0f} |",
f"| **Balance Held** | **${summary['sub_balance_held']:,.0f}** |",
"",
f"**Net Position:** ${summary['net_retention_position']:,.0f}",
"",
"## By Subcontractor",
"",
"| Subcontractor | Trade | Contract | Retained | Released | Held | Status |",
"|---------------|-------|----------|----------|----------|------|--------|"
]
for sub in sorted(self.subcontractors.values(),
key=lambda s: -s.balance_held):
lines.append(
f"| {sub.subcontractor_name} | {sub.trade} | "
f"${sub.contract_value:,.0f} | ${sub.total_retained:,.0f} | "
f"${sub.total_released:,.0f} | ${sub.balance_held:,.0f} | "
f"{sub.status.value} |"
)
# Aged retention
aged = self.get_aged_retention()
if aged:
lines.extend([
"",
"## Aged Retention",
"",
"| Subcontractor | Balance | Days Held |",
"|---------------|---------|-----------|"
])
for item in aged[:10]:
lines.append(
f"| {item['subcontractor_name']} | "
f"${item['balance_held']:,.0f} | {item['days_held']} |"
)
return "\n".join(lines)
from datetime import datetime
# Initialize tracker
tracker = RetentionTracker("Office Tower", default_rate=0.10)
# Add subcontractors
tracker.add_subcontractor("SUB-001", "ABC Mechanical", "HVAC", 500000)
tracker.add_subcontractor("SUB-002", "XYZ Electric", "Electrical", 350000)
# Record billings
tracker.record_billing("SUB-001", 1, datetime(2024, 1, 31), 50000)
tracker.record_billing("SUB-001", 2, datetime(2024, 2, 29), 75000)
tracker.record_billing("SUB-002", 1, datetime(2024, 1, 31), 35000)
# Record owner-level retention
tracker.record_owner_billing(1, datetime(2024, 1, 31), 200000)
# Check release conditions
conditions = tracker.check_release_conditions("SUB-001")
print(f"Missing conditions: {conditions['missing_conditions']}")
# Release retention at substantial completion
tracker.release_retention(
"SUB-001",
ReleaseMilestone.SUBSTANTIAL_COMPLETION,
approved_by="Project Manager",
lien_waivers=True
)
# Generate report
print(tracker.generate_report())
# Forecast releases
forecasts = tracker.forecast_releases(
datetime(2024, 12, 1),
datetime(2025, 1, 15)
)
for f in forecasts[:5]:
print(f"{f['date'].strftime('%Y-%m-%d')}: {f['subcontractor']} - ${f['amount']:,.0f}")
pip install (no external dependencies)
Integration with protocols.io API for managing scientific protocols. This skill should be used when working with protocols.io to search, create, update, or publish protocols; manage protocol steps and materials; handle discussions and comments; organize workspaces; upload and manage files; or integrate protocols.io functionality into workflows. Applicable for protocol discovery, collaborative protocol development, experiment tracking, lab protocol management, and scientific documentation.
Analyzes job descriptions and generates tailored resumes that highlight relevant experience, skills, and achievements to maximize interview chances
Generate Excalidraw diagrams from natural language descriptions. Use when asked to "create a diagram", "make a flowchart", "visualize a process", "draw a system architecture", "create a mind map", or "generate an Excalidraw file". Supports flowcharts, relationship diagrams, mind maps, and system architecture diagrams. Outputs .excalidraw JSON files that can be opened directly in Excalidraw.
Build and distribute Expo development clients locally or via TestFlight
Use when you have a written implementation plan to execute in a separate session with review checkpoints
Data structure for annotated matrices in single-cell analysis. Use when working with .h5ad files or integrating with the scverse ecosystem. This is the data format skill—for analysis workflows use scanpy; for probabilistic models use scvi-tools; for population-scale queries use cellxgene-census.
Benchling R&D platform integration. Access registry (DNA, proteins), inventory, ELN entries, workflows via API, build Benchling Apps, query Data Warehouse, for lab data management automation.
Comprehensive molecular biology toolkit. Use for sequence manipulation, file parsing (FASTA/GenBank/PDB), phylogenetics, and programmatic NCBI/PubMed access (Bio.Entrez). Best for batch processing, custom bioinformatics pipelines, BLAST automation. For quick lookups use gget; for multi-service integration use bioservices.
Take datadrivenconstruction/retention-tracker from the repository into ~/.claude/skills for personal
use, or into .claude/skills inside a project.
The agent identifies a skill by the name field in its header. Two skills with the
same name cannot sit side by side — one of them will be ignored.
The instructions reference pip.
Without those the skill loads but fails at the first command.