Tools

This page lists every MCP tool exposed by formulon-mcp, grouped by purpose. The model receives the same descriptions through MCP tool discovery; this page mirrors them so a human can scan the surface at a glance.

A1 vs zero-based

Unless A1 notation is used, sheet / row / column indices are zero-based to match the Formulon API. Both styles are accepted on tools that take addresses.

Engine

Tool	What it does
formulon_version	Returns the loaded Formulon engine version.
formulon_eval_formula	Evaluates one Excel formula in a throwaway workbook.
formulon_function_lookup	Lists registered functions and resolves metadata or localized names.
formulon_trace	Reads precedents, dependents, or spill info for a cell.

Sessions

Tool	What it does
formulon_open_workbook	Loads an .xlsx path into a new session, or creates a default workbook.
formulon_list_sessions	Lists open workbook sessions.
formulon_close_workbook	Releases a session.
formulon_recalc_session	Triggers a recalculation on an open session.
formulon_save_session	Writes a session to an .xlsx path or returns bytes inline.
formulon_session_metadata	Reads function names or external links from the session.

Inspection

Tool	What it does
formulon_inspect_session	Returns sheets, defined names, tables, and optionally sparse cell entries.
formulon_inspect_layout	Per-sheet layout: used ranges, merges, row / column overrides, protection, cells, calculated values, formulas, and optional style details.
formulon_detect_regions	Detects table-like regions, label-value pairs, and totals with rule-based confidence and evidence.
formulon_analyze_workbook	Classifies workbook shape (invoice, list, report, schedule, form, …) with deterministic evidence.

Cells and ranges

Tool	What it does
formulon_set_cells	Applies mutations to a session. Cells use A1 (Sheet1!B2) or 0-based (sheet / row / col).
formulon_get_cell	Reads one cell, either from a session or directly from a path.
formulon_get_range	Reads an A1 rectangular range from a session.
formulon_find_cells	Searches text cell values and / or formula text.
formulon_replace_cells	Replaces matching text and / or formula text.

Workbook structure

Tool	What it does
formulon_sheet_operation	Adds, removes, renames, or moves sheets.
formulon_set_defined_name	Adds, replaces, or removes workbook-scoped defined names.
formulon_edit_structure	Inserts or deletes rows and columns.
formulon_set_sheet_view	Sets zoom, frozen panes, or sheet-tab hidden state.

Rich workbook data

Tool	What it does
formulon_merge_operation	Lists, adds, removes, or clears merged ranges.
formulon_comment_operation	Gets, sets, or removes cell comments.
formulon_hyperlink_operation	Lists, adds, removes, or clears hyperlinks.
formulon_validation_operation	Lists, adds, removes, or clears data validations.
formulon_conditional_format_operation	Lists, adds, removes, clears, or evaluates conditional formats.

Advanced

Tool	What it does
formulon_workbook_call	Allowlisted low-level access to the Formulon Workbook API.
formulon_inspect_workbook	One-shot summary from path.
formulon_update_workbook	One-shot load / create, mutate, recalculate, save.

workbook_call is allowlisted, not arbitrary

formulon_workbook_call only dispatches methods on the server's allowlist (see Security model). Calls to non-allowlisted methods are rejected. The tool exists for advanced access — PivotTables, PivotCaches, styles, dependency graph queries, function metadata, spill info — that the higher-level tools do not cover yet.

Read next

• Workflow — the canonical loop.
• Security model — what the server will refuse.