How do I install the Fine-Tuning skill?

Run npx skillmds@latest add modbender/fine-tuning in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Fine-Tuning safe to use?

This skill has not completed SkillMD's automated safety review yet. Independent scanners report: SkillSpector: PASS, Skill Scanner: PASS. Capability flags: docs only. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Fine-Tuning?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Fine-Tuning free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Fine-Tuning?

modbender (@modbender) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Fine-Tuning by modbender — Agent Skill

Name: Fine-Tuning
Rating: 4.666666666666667 (3 reviews)
Author: modbender

File contents

When to Use

User wants to fine-tune a language model, evaluate if fine-tuning is worth it, or debug training issues.

Quick Reference

Topic	File
Provider comparison & pricing	`providers.md`
Data preparation & validation	`data-prep.md`
Training configuration	`training.md`
Evaluation & debugging	`evaluation.md`
Cost estimation & ROI	`costs.md`
Compliance & security	`compliance.md`

Core Capabilities

Decide fit — Analyze if fine-tuning beats prompting for the use case
Prepare data — Convert raw data to JSONL, deduplicate, validate format
Select provider — Compare OpenAI, Anthropic (Bedrock), Google, open source based on constraints
Estimate costs — Calculate training cost, inference savings, break-even point
Configure training — Set hyperparameters (learning rate, epochs, LoRA rank)
Run evaluation — Compare fine-tuned vs base model on task-specific metrics
Debug failures — Diagnose loss curves, overfitting, catastrophic forgetting
Handle compliance — Scan for PII, configure on-premise training, generate audit logs

Decision Checklist

Before recommending fine-tuning, ask:

What's the failure mode with prompting? (format, style, knowledge, cost)
How many training examples available? (minimum 50-100)
Expected inference volume? (affects ROI calculation)
Privacy constraints? (determines provider options)
Budget for training + ongoing inference?

Fine-Tune vs Prompt Decision

Signal	Recommendation
Format/style inconsistency	Fine-tune ✓
Missing domain knowledge	RAG first, then fine-tune if needed
High inference volume (>100K/mo)	Fine-tune for cost savings
Requirements change frequently	Stick with prompting
<50 quality examples	Prompting + few-shot

Critical Rules

Data quality > quantity — 100 great examples beat 1000 noisy ones
LoRA first — Never jump to full fine-tuning; LoRA is 10-100x cheaper
Hold out eval set — Always 80/10/10 split; never peek at test data
Same precision — Train and serve at identical precision (4-bit, 16-bit)
Baseline first — Run eval on base model before training to measure actual improvement
Expect iteration — First attempt rarely optimal; plan for 2-3 cycles

Common Pitfalls

Mistake	Fix
Training on inconsistent data	Manual review of 100+ samples before training
Learning rate too high	Start with 2e-4 for SFT, 5e-6 for RLHF
Expecting new knowledge	Fine-tuning adjusts behavior, not knowledge — use RAG
No baseline comparison	Always test base model on same eval set
Ignoring forgetting	Mix 20% general data to preserve capabilities

---name: fine-tuningdescription: Fine-tune LLMs with data preparation, provider selection, cost estimation, evaluation, and compliance checks.--- ## When to Use User wants to fine-tune a language model, evaluate if fine-tuning is worth it, or debug training issues. ## Quick Reference | Topic | File | |-------|------| | Provider comparison & pricing | `providers.md` | | Data preparation & validation | `data-prep.md` | | Training configuration | `training.md` | | Evaluation & debugging | `evaluation.md` | | Cost estimation & ROI | `costs.md` | | Compliance & security | `compliance.md` | ## Core Capabilities 1. **Decide fit** — Analyze if fine-tuning beats prompting for the use case 2. **Prepare data** — Convert raw data to JSONL, deduplicate, validate format 3. **Select provider** — Compare OpenAI, Anthropic (Bedrock), Google, open source based on constraints 4. **Estimate costs** — Calculate training cost, inference savings, break-even point 5. **Configure training** — Set hyperparameters (learning rate, epochs, LoRA rank) 6. **Run evaluation** — Compare fine-tuned vs base model on task-specific metrics 7. **Debug failures** — Diagnose loss curves, overfitting, catastrophic forgetting 8. **Handle compliance** — Scan for PII, configure on-premise training, generate audit logs ## Decision Checklist Before recommending fine-tuning, ask: - [ ] What's the failure mode with prompting? (format, style, knowledge, cost) - [ ] How many training examples available? (minimum 50-100) - [ ] Expected inference volume? (affects ROI calculation) - [ ] Privacy constraints? (determines provider options) - [ ] Budget for training + ongoing inference? ## Fine-Tune vs Prompt Decision | Signal | Recommendation | |--------|----------------| | Format/style inconsistency | Fine-tune ✓ | | Missing domain knowledge | RAG first, then fine-tune if needed | | High inference volume (>100K/mo) | Fine-tune for cost savings | | Requirements change frequently | Stick with prompting | | <50 quality examples | Prompting + few-shot | ## Critical Rules - **Data quality > quantity** — 100 great examples beat 1000 noisy ones - **LoRA first** — Never jump to full fine-tuning; LoRA is 10-100x cheaper - **Hold out eval set** — Always 80/10/10 split; never peek at test data - **Same precision** — Train and serve at identical precision (4-bit, 16-bit) - **Baseline first** — Run eval on base model before training to measure actual improvement - **Expect iteration** — First attempt rarely optimal; plan for 2-3 cycles ## Common Pitfalls | Mistake | Fix | |---------|-----| | Training on inconsistent data | Manual review of 100+ samples before training | | Learning rate too high | Start with 2e-4 for SFT, 5e-6 for RLHF | | Expecting new knowledge | Fine-tuning adjusts behavior, not knowledge — use RAG | | No baseline comparison | Always test base model on same eval set | | Ignoring forgetting | Mix 20% general data to preserve capabilities |

Frequently asked questions

Fine-Tuning