# Gantt Chart Generator > Use this skill whenever the user asks to visualize a project schedule, timeline, Gantt chart, or phase/task breakdown over time. It gives the agent a prebuilt, parameterized gantt() function so Gantt charts are produced instantly and consistently — with colour-coded groups, completion overlays, a today reference line, and auto-scaled date axes — instead of hand-writing matplotlib each time. - Skill: `kody-w/gantt-chart-generator` (Agent Skill, multi-file: 5 files) - Install (CLI): `npx skillmds@latest add kody-w/gantt-chart-generator` - Raw SKILL.md: https://api.skillmd.com/api/skills/kody-w/gantt-chart-generator/raw - Safety review: pending - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: AI & ML - Author: kody-w (https://skillmd.com/u/kody-w) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/kody-w/gantt-chart-generator --- Generate horizontal Gantt charts from schedule data via the bundled `scripts/gantt.py` toolkit. The `gantt()` function accepts a DataFrame or file path plus column names, and saves a PNG (returning the path). It handles theming, date parsing, bar colour-coding, completion overlays, today-line, legend, and saving. ## Instructions 1. Provide the data source: a pandas DataFrame, or a path to a `.csv` / `.tsv` / `.json` file. - One row = one task / phase. - Required columns: a **phase/task name** column, a **start date** column, and either an **end date** column OR a **duration-in-days** column. 2. Import and call `gantt()`: ```python import sys sys.path.insert(0, "scripts") # adjust path to where gantt.py is deployed from gantt import gantt # Basic — start + end columns gantt("schedule.csv", phase="Phase", start="Start", end="End", title="Project Schedule", out="gantt.png") # Group colour-coding + today line gantt(df, phase="phase", start="planned_start", end="planned_end", group="project", today=True, out="schedule.png") # Duration instead of end date gantt(df, phase="task", start="start_date", duration="days", out="schedule.png") # Completion % hatch overlay gantt(df, phase="Phase", start="Start", end="End", completion="PctDone", out="gantt.png") ``` 3. See `references/cheatsheet.md` for full parameter reference and CLI examples. ## Bundled files - `scripts/gantt.py` — the full toolkit (load_data, apply_theme, save_fig, gantt, CLI) - `references/cheatsheet.md` — parameter quick-reference and copy-paste examples - `assets/sample_schedule.csv` — demo dataset that exercises every feature ## Defaults & behaviour - Colorblind-friendly palette (matches chart-builder skill for visual consistency). - Date axis auto-scales: weekly ticks ≤90 days, monthly ≤365 days, bi-monthly beyond. - Bars ordered top-to-bottom matching input row order. - Rows with missing phase or start values are silently dropped before drawing. - Output PNG at 150 DPI by default. - Provide `end` OR `duration` — not both; `end` takes priority if both are present. ## Run this — do not improvise This capability's deterministic implementation is a RAPP single-file agent, linked beside this file as `gantt_chart_generator_agent.py` and embedded as the fenced Python below (sha256 301a1e3447da6048…; a byte-exact copy is also vaulted in the capsule comment at the end of this file). On a host with sandbox execution, run the linked file directly — if it is missing, write the fence contents verbatim to `gantt_chart_generator_agent.py` first: ```bash python3 gantt_chart_generator_agent.py '{"key": "value"}' # arguments as one JSON object echo '{"key": "value"}' | python3 gantt_chart_generator_agent.py # or on stdin python3 gantt_chart_generator_agent.py --tool # emit the JSON tool contract ``` Treat stdout as a tool result. If it reports missing or unresolved inputs, stop and collect them. If it returns `steps`, execute those steps in order exactly as returned; if it returns `instructions`, follow them with the supplied inputs. Otherwise use the result verbatim. Do not invent behavior beyond that output. On a host without code execution, treat the Parameters schema and the code below as the exact specification and never paraphrase a step. Never edit inside the generated markers; a converter-equipped host can instead restore the original file checksum-verified with the installed `rapp-agent-converter/scripts/toast.py convert SKILL.md --to agent`. ````python # rapp:deterministic """GanttChartGenerator -- Use this skill whenever the user asks to visualize a project schedule, timeline, Gantt chart, or phase/task breakdown over time. It gives the agent a prebuilt, parameterized gantt() function so Gantt charts are produced instantly and consistently — with colour-coded groups, completion overlays, a today reference line, and auto-scaled date axes — instead of hand-writing matplotlib each time. Generated by the rapp skill from gantt-chart-generator. The RCI capsule at the bottom of this file carries the full original; `toast.py convert` restores it byte-exact.""" import json import re import sys try: from agents.basic_agent import BasicAgent except ImportError: # running OUTSIDE a brainstem -- stay executable anyway. class BasicAgent: # noqa: D101 - minimal stand-in, same contract def __init__(self, name=None, metadata=None): if name: self.name = name if metadata: self.metadata = metadata def perform(self, **kwargs): return "Not implemented." def system_context(self): return None def to_tool(self): return {"type": "function", "function": { "name": self.name, "description": self.metadata.get("description", ""), "parameters": self.metadata.get("parameters", {})}} # The procedural layer, verbatim from the source capability. INSTRUCTIONS = 'Generate horizontal Gantt charts from schedule data via the bundled `scripts/gantt.py` toolkit.\nThe `gantt()` function accepts a DataFrame or file path plus column names, and saves a PNG (returning the path).\nIt handles theming, date parsing, bar colour-coding, completion overlays, today-line, legend, and saving.\n\n## Instructions\n\n1. Provide the data source: a pandas DataFrame, or a path to a `.csv` / `.tsv` / `.json` file.\n - One row = one task / phase.\n - Required columns: a **phase/task name** column, a **start date** column, and either an **end date** column OR a **duration-in-days** column.\n\n2. Import and call `gantt()`:\n\n```python\nimport sys\nsys.path.insert(0, "scripts") # adjust path to where gantt.py is deployed\nfrom gantt import gantt\n\n# Basic — start + end columns\ngantt("schedule.csv", phase="Phase", start="Start", end="End",\n title="Project Schedule", out="gantt.png")\n\n# Group colour-coding + today line\ngantt(df, phase="phase", start="planned_start", end="planned_end",\n group="project", today=True, out="schedule.png")\n\n# Duration instead of end date\ngantt(df, phase="task", start="start_date", duration="days",\n out="schedule.png")\n\n# Completion % hatch overlay\ngantt(df, phase="Phase", start="Start", end="End",\n completion="PctDone", out="gantt.png")\n```\n\n3. See `references/cheatsheet.md` for full parameter reference and CLI examples.\n\n## Bundled files\n- `scripts/gantt.py` — the full toolkit (load_data, apply_theme, save_fig, gantt, CLI)\n- `references/cheatsheet.md` — parameter quick-reference and copy-paste examples\n- `assets/sample_schedule.csv` — demo dataset that exercises every feature\n\n## Defaults & behaviour\n- Colorblind-friendly palette (matches chart-builder skill for visual consistency).\n- Date axis auto-scales: weekly ticks ≤90 days, monthly ≤365 days, bi-monthly beyond.\n- Bars ordered top-to-bottom matching input row order.\n- Rows with missing phase or start values are silently dropped before drawing.\n- Output PNG at 150 DPI by default.\n- Provide `end` OR `duration` — not both; `end` takes priority if both are present.' # Ordered commands lifted verbatim from the capability's own documentation. STEPS = [] class GanttChartGeneratorAgent(BasicAgent): def __init__(self): self.name = 'GanttChartGenerator' self.metadata = { "name": "GanttChartGenerator", "description": "Use this skill whenever the user asks to visualize a project schedule, timeline, Gantt chart, or phase/task breakdown over time. It gives the agent a prebuilt, parameterized gantt() function so Gantt charts are produced instantly and consistently \u2014 with colour-coded groups, completion overlays, a today reference line, and auto-scaled date axes \u2014 instead of hand-writing matplotlib each time.", "parameters": { "type": "object", "properties": {}, "required": [] } } super().__init__(name=self.name, metadata=self.metadata) def perform(self, **kwargs): # toaster:generated-perform return json.dumps({"status": "ok", "instructions": INSTRUCTIONS, "inputs": kwargs, "note": "Prose-only capability: follow INSTRUCTIONS " "with the given inputs."}, indent=2) if __name__ == "__main__": # echo '{"arg": "value"}' | python3 gantt_chart_generator_agent.py # python3 gantt_chart_generator_agent.py '{"arg": "value"}' # python3 gantt_chart_generator_agent.py --tool # emit the JSON tool contract _a = sys.argv[1:] if _a and _a[0] == "--tool": print(json.dumps(GanttChartGeneratorAgent().to_tool(), indent=2)) else: _raw = _a[0] if _a else (sys.stdin.read().strip() or "{}") print(GanttChartGeneratorAgent().perform(**json.loads(_raw))) # rci-capsule:v1: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 ````