Google Docs: Style a text range — MCP tool

Google Docs MCP tool: Applies character formatting — bold, fonts, colors, links — to an index range.

Technical name: style_text

What task it solves

I want to format a passage of text.

Applies character formatting — bold, fonts, colors, links — to an index range.

When to use it

Use it after inserting or locating text: bold/italic/underline/strikethrough, small caps, font size and family, text and highlight colors, links (or link removal) and superscript/subscript. Styling does not shift indexes, so several calls can reuse the same coordinates.

What to provide

• document_id, start_index, end_index — required.
• Any of: bold, italic, underline, strikethrough, small_caps (booleans), font_size (points), font_family, foreground_color / background_color (6-digit hex), link_url (empty string removes a link), baseline_offset (none/superscript/subscript). At least one is required.
• tab_id, segment_id — optional addressing.

What it returns

The batchUpdate reply with the new revisionId.

What changes in Google Docs

Only the provided style fields change on the range (the fields mask is computed); explicit false turns a toggle off. Other formatting is untouched.

Example request

Make the phrase "due Friday" bold and red in the status update.

Errors and limitations

Requires at least one style field. Colors must be 6-digit hex. Replaying the same style converges (idempotent), but the range must still be current.

Access also depends on token permissions, quotas, and upstream API limits.

Related MCP tools

• Style paragraphs — style_paragraph
• Read document as text — read_document_text

Technical details

• Impact: destructive operation
• Group: Styles and lists
• Description source: style_text registration in src/tools/styles.ts
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