Agentic Plugin Marketplace is a collection of reusable plugins, agents, skills, commands, and rules for coding-agent tools including Claude Code, Codex CLI, Cursor, OpenCode, Antigravity CLI, and GitHub Copilot. It is for developers assembling agentic workflows across multiple harnesses from shared Markdown sources, and the catalogue entries are examples or subsets of those workflow components.
Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx agentmods add skills/wshobson/agents/spark-optimizationnpx skills add wshobson/agents --skill spark-optimizationgit clone --depth 1 https://github.com/wshobson/agentsWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/wshobson/agents/spark-optimization)<a href="https://agentmods.dev/skills/wshobson/agents/spark-optimization"><img src="https://agentmods.dev/badge/skills/wshobson/agents/spark-optimization.svg" alt="Measured on agentmods" height="20"></a>What it costs to keep this loaded
Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00037 | $0.00720 |
| Opus 5 | $0.00018 | $0.00360 |
| Sonnet 5 | $0.00007 | $0.00144 |
| Haiku 4.5 | $0.00004 | $0.00072 |
Grade A, and why
spark-optimization scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2d ago.
A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.
Nothing flagged
None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.
Copies of this mod
1 near-identical copy found in the catalogue:
- wshobson-spark-optimization — 95% identical, 1 lines differ
How it starts
The opening of the file, as written. The whole thing — 96 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Apache Spark Optimization
Production patterns for optimizing Apache Spark jobs including partitioning strategies, memory management, shuffle optimization, and performance tuning.
When to Use This Skill
- Optimizing slow Spark jobs
- Tuning memory and executor configuration
- Implementing efficient partitioning strategies
- Debugging Spark performance issues
- Scaling Spark pipelines for large datasets
- Reducing shuffle and data skew
Core Concepts
1. Spark Execution Model
Driver Program
↓
Job (triggered by action)
↓
Stages (separated by shuffles)
↓
Tasks (one per partition)
2. Key Performance Factors
| Factor | Impact | Solution |
|---|---|---|
| Shuffle | Network I/O, disk I/O | Minimize wide transformations |
| Data Skew | Uneven task duration | Salting, broadcast joins |
| Serialization | CPU overhead | Use Kryo, columnar formats |
| Memory | GC pressure, spills | Tune executor memory |
| Partitions | Parallelism | Right-size partitions |
Quick Start
from pyspark.sql import SparkSession
from pyspark.sql import functions as F
# Create optimized Spark session
spark = (SparkSession.builder
.appName("OptimizedJob")
.config("spark.sql.adaptive.enabled", "true")
.config("spark.sql.adaptive.coalescePartitions.enabled", "true")
.config("spark.sql.adaptive.skewJoin.enabled", "true")
.config("spark.serializer", "org.apache.spark.serializer.KryoSerializer")
.config("spark.sql.shuffle.partitions", "200")
.getOrCreate())
# Read with optimized settings
df = (spark.read
.format("parquet")
.option("mergeSchema", "false")
.load("s3://bucket/data/"))
# Efficient transformations
result = (df
.filter(F.col("date") >= "2024-01-01")
.select("id", "amount", "category")
.groupBy("category")
.agg(F.sum("amount").alias("total")))
result.write.mode("overwrite").parquet("s3://bucket/output/")
What ships with it
1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
What this file has done since we first saw it
Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.
- 2d ago First seen · 96 lines · 37 tokens per session scan A 6af24df5e512
spark-optimization is a skill published in the GitHub repository wshobson/agents (39,449 stars, last pushed 4d ago), licensed MIT. It adds 37 tokens to every session and 720 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-09-03.
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