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Streaming Tools

What Changed?

In v3.x, there were 3 separate streaming tools. In v4.0.0, their logic is embedded into the primary tools:

v3 Tool (removed)	v4 Replacement	Notes
`streaming_write_file`	`mcp_write`	Auto-streams when content > 50KB
`chunked_read_file`	`mcp_read`	Auto-chunks when file > 50KB
`smart_edit_file`	`mcp_edit`	Auto line-by-line for large files

How It Works Now

You don’t need to choose between streaming and non-streaming tools. The mcp_* tools automatically detect file size and select the optimal strategy:

Small files (< 100KB): Direct I/O — fastest possible
Large files (> 100KB): Streaming I/O — prevents timeouts

Example

// This AUTOMATICALLY streams for large content:
mcp_write({ path: "report.json", content: largeJsonData })
// Progress: 20%... 50%... 75%... 100%
// Complete in 8 seconds

// This AUTOMATICALLY chunks for large files:
mcp_read({ path: "huge_log.txt" })
// Reads in 64KB chunks internally

// This AUTOMATICALLY uses line-by-line for large files:
mcp_edit({ path: "config.xml", old_text: "old", new_text: "new" })
// Processes line by line, never loads entire file

Performance

File Size	v3 (manual selection needed)	v4 (automatic)
10 KB	Use `write_file`	Use `mcp_write`
500 KB	Use `streaming_write_file`	Use `mcp_write`
5 MB	Use `streaming_write_file`	Use `write_file`

Same performance, zero cognitive overhead.

See Also

Core Tools — Complete API reference for all 16 tools
Migration from v3 — Full migration guide