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1.4Skills vs. Other Approaches
| Approach | What It Does | Token Cost | Complexity |
|---|---|---|---|
| Built-in tools | Agent's native capabilities (Bash, Read, Write) | Zero (always loaded) | None |
| Agent Skills | Markdown instructions injected into context | Low (~1,000 tokens once) | Low (one file) |
| MCP Servers | External processes exposing tool schemas over a protocol | High (schemas on every turn) | Medium (server process) |
| Custom code | Agent writes and runs automation code directly | Variable | High (error-prone) |
Skills occupy a sweet spot: light enough not to burden the context window, powerful enough to teach complex domain workflows.