How do I install Spreadsheet Kit MCP?

Copy the stdio config for Cursor, Claude Desktop, Claude Code, or VS Code on this page. It uses the publisher's install, not a PlugMCP proxy.

Does Spreadsheet Kit MCP need an API key?

No required environment variable is listed on this record.

What transport does Spreadsheet Kit MCP use?

Spreadsheet Kit MCP runs locally over stdio.

When was Spreadsheet Kit MCP last checked?

Last checked 2026-11-09. Agent-safe Excel workbook analysis, editing, recalc, and verification tools.

Spreadsheet Kit MCP server

agent-spreadsheet

agent-spreadsheet is the tool interaction service for agent-based spreadsheet usage.

It gives agents a safe, inspectable, token-efficient way to read, analyze, mutate, verify, and operationalize Excel workbooks without falling back to brittle UI automation.

If you want an agent to work with spreadsheets like a real system instead of a screenshot puppet, this is the stack.

What this project is

agent-spreadsheet ships a unified spreadsheet interaction layer across three surfaces:

Surface	Binary / Package	Mode	Best for
CLI	`agent-spreadsheet` / `asp`	Stateless files + resident sessions	One-shot pipelines or retained multi-turn workbook editing
MCP server	`agent-spreadsheet-mcp`	Stateful	Multi-turn agent sessions, workbook caching, fork/recalc workflows
TypeScript SDK	`agent-spreadsheet-sdk`	Library	App integrations — drives the server's canonical `/v1` route, or runs fully in-process via the embedded WASM engine (no server required)

The WASM build (agent-spreadsheet-wasm) is the SDK's local runtime, not a separate product surface: JS and TypeScript code targets one object model and the execution substrate (server vs embedded engine) is a configuration choice.

In 0.16 these surfaces share the resident Rust document/evaluator runtime and 32-operation registry. Explicit native sessions automatically start a private journal-backed host. SDK/WASM and genuine just-bash sessions retain their history in memory; XLSX export saves a document snapshot, not a restartable session journal. Warm edit/recalculate/read loops avoid XLSX serialization and repeated evaluator ingestion. See runtime guarantees and limits and the SDK/just-bash examples.

Supported workbook modes:

.xlsx / .xlsm — read + write
.xls / .xlsb — discovery/read-oriented workflows only

Powered by Formualizer

Default in-process calculation uses Formualizer — a permissively licensed (MIT/Apache-2.0) spreadsheet engine written in Rust: formula parsing, dependency-graph recalculation, 400+ Excel functions, dynamic arrays, and deterministic evaluation built for agents. No Excel COM or headless LibreOffice is required. Optional LibreOffice integration remains available, but Formualizer is the release-critical backend.

That native engine is why this project can offer what most spreadsheet tooling for agents cannot: recalculate the actual workbook, trace which cells changed and why, and prove it — not just read cached values or push blind edits.

Embedding spreadsheet logic in your own product rather than driving workbooks as an agent? Use Formualizer directly (Rust, Python, JS/WASM).

Why agents use agent-spreadsheet

Built for tool use, not just humans

deterministic JSON contracts
schema and example discovery from the CLI itself
explicit pagination and compact output modes
machine-readable warnings and error envelopes

Safe mutation, not blind mutation

dry-run first workflows
stateless output modes and overwrite safety
event-sourced session editing
verification surfaces for proving downstream outcomes
structural impact analysis before risky workbook changes

Spreadsheet-aware, not generic file editing

region detection
table and footer-aware append helpers
template row / row band cloning
formula-specific replace and diagnostics
named range CRUD
recalculation + diff + proof flows

Good agent ergonomics

nested command groups with legacy alias compatibility
token-efficient reads
exact-cell inspection and layout inspection
workflow helpers for the repetitive parts agents usually get wrong

What is new / what makes this stack different

The current surface is much stronger than a plain “read some cells” tool. Major capabilities now include:

asp as the primary CLI with agent-spreadsheet preserved as a compatibility alias
grouped verification via asp verify proof and asp verify diff
preview-first workflow helpers for:
- write append
- write clone-template-row
- write clone-row-band
formula-safe batch workflows with parse-policy diagnostics
cell/layout/export/import inspection surfaces
named range management (write name define|update|delete)
formula-only replacement (write formulas replace)
event-sourced session editing with log, branch, undo/redo, fork, apply, and materialize
SheetPort manifest lifecycle + execution for contract-driven spreadsheet automation

Install

Shell installer

curl -fsSL https://raw.githubusercontent.com/PSU3D0/agent-spreadsheet/main/install.sh | sh

The installer downloads a prebuilt CLI to ~/.local/bin and creates the asp command. Pin a release with ASP_VERSION=0.16.0, set ASP_INSTALL_DIR to choose another destination, or pass --mcp to install the MCP server too:

curl -fsSL https://raw.githubusercontent.com/PSU3D0/agent-spreadsheet/main/install.sh | sh -s -- --mcp

npm

npm i -g agent-spreadsheet

This installs both asp (the primary command) and agent-spreadsheet (the compatibility alias) from a prebuilt native binary. No Rust toolchain is required.

cargo-binstall

cargo binstall agent-spreadsheet

This installs the prebuilt CLI in seconds.

Cargo

cargo install agent-spreadsheet --features recalc --bin asp --bin agent-spreadsheet

This builds the CLI from source. Formualizer (the native Rust recalc engine) is included by default.

mise

mise use -g "ubi:PSU3D0/agent-spreadsheet[exe=asp]"

# Homebrew
brew install psu3d0/tap/agent-spreadsheet

MCP server

cargo install agent-spreadsheet-mcp

Docker

# Read-only / slim
docker pull ghcr.io/psu3d0/agent-spreadsheet-mcp:latest

# Write + recalc + screenshots
docker pull ghcr.io/psu3d0/agent-spreadsheet-mcp:latest-full

JavaScript SDK

npm i agent-spreadsheet-sdk

Prebuilt binaries

Download raw binaries and archives from GitHub Releases.

Published native assets include:

Linux x86_64
Linux arm64
macOS x86_64
macOS arm64
Windows native binaries are not shipped for 0.16; native release validation targets Linux and macOS

Start here: the core workflows

1) Orient the workbook before reading cells

# What sheets are here?
asp read sheets data.xlsx

# What regions/tables/parameter blocks does this sheet contain?
asp read overview data.xlsx "Model"

# What named items are available?
asp read names data.xlsx

# Read a structured region as a table
asp read table data.xlsx --sheet "Model"

2) Inspect exactly what an agent needs

# Raw values for exact ranges
asp read values data.xlsx Model A1:C20

# Detail-view for targeted cells (value / formula / cached / style triage)
asp read cells data.xlsx Model B2 D10:F12

# Layout-aware rendering for a bounded range
asp read layout data.xlsx Model --range A1:H30 --render both

# Export a bounded range to csv or grid json
asp read export data.xlsx Model A1:H30 --format csv --output model.csv

3) Do a safe stateless edit → recalc → proof → diff loop

asp workbook copy data.xlsx /tmp/draft.xlsx
asp write cells /tmp/draft.xlsx Inputs "B2=500" "C2==B2*1.1"
asp workbook recalculate /tmp/draft.xlsx
asp verify proof data.xlsx /tmp/draft.xlsx --targets Summary!B2,Summary!B3 --named-ranges
asp verify diff data.xlsx /tmp/draft.xlsx --details --limit 50

A representative label-mode lookup:

asp analyze find-value data.xlsx "Net Income" --mode label --label-direction below

4) Preview structural risk before mutating the workbook

asp analyze ref-impact data.xlsx --ops @structure_ops.json --show-formula-delta

This is intentionally read-only. It surfaces shifted spans, absolute-reference warnings, token counts, and optional before/after formula samples.

5) Use workflow helpers instead of reinventing row logic

# Stateless batch writes
asp write batch transform data.xlsx --ops @ops.json --dry-run
asp write batch style data.xlsx --ops @style_ops.json --dry-run

# Append rows into a detected region or table, respecting footer rows when present
asp write append data.xlsx --sheet Revenue --table-name RevenueTable --from-csv rows.csv --header --dry-run

# Clone one template row with preview-first planning
asp write clone-template-row data.xlsx --sheet Inputs --source-row 8 --after 8 --count 3 --dry-run

# Clone a contiguous row band repeatedly
asp write clone-row-band data.xlsx --sheet Forecast --source-rows 12:16 --after 16 --repeat 4 --dry-run

6) Use a stateful session when the edit story gets complex

asp session start --base data.xlsx --workspace .
asp session op --session <id> --ops @edit.json --workspace .
asp session apply --session <id> <staged_id> --workspace .
asp session materialize --session <id> --output result.xlsx --workspace .

And when you need proper history and branching:

asp session log --session <id> --workspace .
asp session fork --session <id> scenario-a --workspace .
asp session undo --session <id> --workspace .
asp session redo --session <id> --workspace .
asp session checkout --session <id> <op_id> --workspace .

7) Turn workbook interfaces into contracts with SheetPort

# Discover candidate ports from workbook structure
asp sheetport manifest candidates model.xlsx

# Validate or normalize a manifest
asp sheetport manifest validate manifest.yaml
asp sheetport manifest normalize manifest.yaml

# Bind-check a workbook against a manifest
asp sheetport bind-check model.xlsx manifest.yaml

# Execute the manifest with JSON inputs
asp sheetport run model.xlsx manifest.yaml --inputs @inputs.json

CLI overview

The primary CLI is asp.

agent-spreadsheet remains available as a compatibility alias, so both of these are valid:

asp read sheets data.xlsx
agent-spreadsheet read sheets data.xlsx

Preferred command groups

asp read ...
asp analyze ...
asp write ...
asp workbook ...
asp verify ...
asp session ...
asp sheetport ...

Legacy aliases

Legacy flat commands are still normalized to the new nested surface where practical. That makes migration easier for older prompts, docs, and automation.

Discoverability built into the CLI

When an agent is unsure of payload shape, it can ask the tool directly:

asp operations                  # CLI-supported runtime subset
asp registry --all              # complete host-independent registry + schemas
asp schema read_cells
asp example read_cells
asp schema write batch transform
asp example write batch transform
asp schema session op transform.write_matrix
asp example session op transform.write_matrix

Canonical machine calls use the same registry and dispatcher as other surfaces. asp schema <canonical-op> and asp example <canonical-op> project the native adapter contract: resource_id and, for verification, baseline_resource_id are omitted from required JSON because --bind and --baseline inject ephemeral resources. The host-independent asp registry --all remains unchanged.

asp op read_cells --bind data.xlsx --json '{"sheet_name":"Sheet1","selection":{"kind":"range","ranges":["A1:C10"]}}'
asp op verify_workbook --baseline base.xlsx --bind current.xlsx --json '{}'
echo '{"action":"schema"}' | asp op sheetport_manifest

--bind reads the current workbook, while --baseline supplies the second workbook only for verify_workbook. Canonical mutable CLI calls require exactly one persistence target: --output <path> writes a new file or --in-place atomically replaces the bound file; pure preview persists nothing and accepts neither. Durable fork, checkpoint, stage, and history operations are intentionally absent from stateless CLI discovery. This is a core design principle: the surface should explain itself to the agent.

Command families

`read` — extraction and inspection

Command	Purpose
`asp read sheets <file>`	List sheets with summary metadata
`asp read overview <file> <sheet>`	Detect regions, headers, and orientation
`asp read values <file> <sheet> <range> [range...]`	Pull raw values for exact A1 ranges
`asp read export <file> <sheet> <range>`	Export a bounded range to csv or grid json
`asp read cells <file> <sheet> <target> [target...]`	Inspect exact cells/ranges with value/formula/cached/style snapshots
`asp read page <file> <sheet> ...`	Deterministic sheet paging with `next_start_row`
`asp read table <file> ...`	Structured table/region read with deterministic `next_offset`
`asp read names <file>`	Named ranges, named formulas, and table items
`asp read workbook <file>`	Workbook-level metadata
`asp read layout <file> <sheet>`	Layout-aware rendering with widths, merges, borders, and optional ascii output

Why these matter for agents

Agents rarely need “the whole spreadsheet.” They need:

the right region
the right page
the right cells
just enough layout to understand intent

That is why the read surface combines region detection, structured reads, detail inspection, and explicit continuation.

`analyze` — search, diagnostics, and impact understanding

Command	Purpose
`asp analyze find-value <file> <query>`	Search by value or by label semantics
`asp analyze find-formula <file> <query>`	Text search within formulas
`asp analyze formula-map <file> <sheet>`	Summarize formulas by complexity/frequency
`asp analyze formula-trace <file> <sheet> <cell> <precedents\|dependents>`	Dependency tracing with continuation
`asp analyze scan-volatiles <file>`	Find volatile formulas
`asp analyze sheet-statistics <file> <sheet>`	Density and type statistics
`asp analyze table-profile <file>`	Header/type/cardinality profiling
`asp analyze ref-impact <file> --ops @structure_ops.json`	Preflight structural edit impact without mutation

Why this matters

Headless spreadsheet automation wins when it can explain consequences, not just execute mutations. ref-impact, formula-trace, and grouped diagnostics are all part of that story.

`write` — safe mutations and workflow helpers

Command	Purpose
`asp write cells <file> <sheet> ...`	Direct shorthand cell edits
`asp write import <file> <sheet> ...`	Import grid json or csv into a workbook range
`asp write append ...`	Footer-aware row append into a region or table
`asp write clone-template-row ...`	Clone one template row with preview-first planning
`asp write clone-row-band ...`	Clone a multi-row template band repeatedly
`asp write formulas replace ...`	Formula-only find/replace on a sheet/range
`asp write name define	update
`asp write batch transform ...`	Stateless transform pipeline
`asp write batch style ...`	Stateless style edits
`asp write batch formula-pattern ...`	Autofill-like formula application
`asp write batch structure ...`	Rows/cols/sheets/copy/move style mutations
`asp write batch column-size ...`	Column width operations
`asp write batch sheet-layout ...`	Freeze panes, zoom, page setup, print area
`asp write batch rules ...`	Data validation + conditional formatting

Safety model

Most mutating commands support a strict mode matrix:

--dry-run
--in-place
--output <PATH>

This matters for agents because it allows:

dry-run planning
non-destructive execution
explicit overwrite control

Formula maintenance

Formula mutation is now a first-class surface:

asp write formulas replace data.xlsx Sheet1 --find '$64' --replace '$65' --dry-run
asp write formulas replace data.xlsx Sheet1 --find 'Sheet1!' --replace 'Sheet2!' --range A1:Z100 --output fixed.xlsx

Named range maintenance

asp write name define data.xlsx RevenueInput 'Inputs!$B$2'
asp write name update data.xlsx RevenueInput 'Inputs!$B$2:$B$4' --in-place
asp write name delete data.xlsx RevenueInput --in-place

`workbook` — file-level flows

Command	Purpose
`asp workbook create <path>`	Create a new workbook
`asp workbook copy <source> <dest>`	Safe copy for edit workflows
`asp workbook recalculate <file>`	Recalculate formulas via the configured backend

`verify` — proof, not vibes

Command	Purpose
`asp verify proof <baseline> <current>`	Prove target deltas and isolate new/resolved/preexisting errors
`asp verify diff <original> <modified>`	Summary-first grouped workbook diff with optional paged details

Why verification matters

Most spreadsheet automation tools stop at “the edit applied.”

agent-spreadsheet goes further:

did the target cells change the way we expected?
did the workbook introduce new errors?
which changes were direct edits vs recalculation fallout?
what changed overall, grouped in a way an agent can reason about?

This verification layer is a big part of why this project is a serious agent substrate rather than a utility script.

`session` — event-sourced stateful editing

The session surface is for workflows that are too complex for a single stateless write.

What sessions give you

persistent editing state
staged dry-run operations
compare-and-swap apply semantics
logs and replayability
branch/switch/fork flows
undo / redo / checkout
explicit materialization back to a workbook file

Canonical loop

asp session start --base model.xlsx --workspace .
asp session op --session <id> --ops @ops.json --workspace .
asp session apply --session <id> <staged_id> --workspace .
asp session materialize --session <id> --output result.xlsx --workspace .

History and branching

asp session log --session <id> --workspace .
asp session branches --session <id> --workspace .
asp session fork --session <id> experiment-b --workspace .
asp session switch --session <id> experiment-b --workspace .
asp session undo --session <id> --workspace .
asp session redo --session <id> --workspace .
asp session checkout --session <id> <op_id> --workspace .

Use sessions when you want repeatability, auditability, and multi-step safety.

`sheetport` — spreadsheet interfaces as executable contracts

SheetPort is the workflow surface for turning workbook inputs/outputs into explicit machine contracts.

Manifest lifecycle

asp sheetport manifest candidates model.xlsx
asp sheetport manifest schema
asp sheetport manifest validate manifest.yaml
asp sheetport manifest normalize manifest.yaml

Bind-check + run

asp sheetport bind-check model.xlsx manifest.yaml
asp sheetport run model.xlsx manifest.yaml --inputs @inputs.json --freeze-volatile

Use this when you want a workbook to behave less like an opaque file and more like a declared service interface.

Output contracts for agents

Canonical vs compact shapes

All commands default to JSON. Many also support:

--shape canonical
--shape compact

Policy:

canonical keeps the full stable schema
compact removes wrapper noise where the contract allows it while preserving continuation fields and command-specific semantics

Shape policy:

Canonical (default): preserve the full response schema.
range-values: returns a stable values: [...] envelope in both canonical and compact modes.
range-values default encoding: dense JSON (dense.encoding = "dense_v1") with dictionary + run-length row_runs.
range-values --include-formulas: includes sparse formula coordinates in dense mode (dense.formulas), or a matrix in explicit json format.
read-table and sheet-page: compact preserves the active branch and continuation fields (next_offset, next_start_row).
formula-trace compact: omits per-layer highlights while preserving layers and next_cursor.

Deterministic pagination loops

# sheet-page continuation
asp read page data.xlsx Sheet1 --format compact --page-size 200
asp read page data.xlsx Sheet1 --format compact --page-size 200 --start-row 201

# read-table continuation
asp read table data.xlsx --sheet "Sheet1" --table-format values --limit 200 --offset 0
asp read table data.xlsx --sheet "Sheet1" --table-format values --limit 200 --offset 200

`sheet-page` machine contract

Inspect top-level format before reading payload fields.
format=full: read top-level rows plus optional header_row and next_start_row.
format=compact: read compact.headers, compact.header_row, compact.rows plus optional next_start_row.
format=values_only: read values_only.rows plus optional next_start_row.
Continuation is always driven by top-level next_start_row when present.
Global --shape compact preserves the active sheet-page branch; it does not flatten sheet-page payloads.

Machine continuation example:

Request page 1 without --start-row.
If next_start_row is present, call sheet-page again with --start-row <next_start_row>.
Stop when next_start_row is omitted.

Self-describing payloads

When the agent is unsure what to send, ask for a schema or example:

asp schema write batch rules
asp example write batch rules
asp schema session op structure.insert_rows
asp example session op structure.insert_rows

Batch payload examples

All batch payloads use a top-level envelope object. Most commands require {"ops":[...]}; column-size-batch prefers {"sheet_name":"...","ops":[...]} and also accepts per-op sheet_name inside {"ops":[...]}.

transform-batch payloads (`@transform_ops.json`)

Minimal: {"ops":[{"kind":"fill_range","sheet_name":"Sheet1","target":{"kind":"range","range":"B2:B4"},"value":"0"}]}
Advanced: {"ops":[{"kind":"replace_in_range","sheet_name":"Sheet1","target":{"kind":"region","region_id":1},"find":"N/A","replace":"","match_mode":"contains","case_sensitive":false,"include_formulas":true}]}

style-batch payloads (`@style_ops.json`)

Minimal: {"ops":[{"sheet_name":"Sheet1","target":{"kind":"range","range":"B2:B2"},"patch":{"font":{"bold":true}}}]}
Advanced: {"ops":[{"sheet_name":"Sheet1","target":{"kind":"cells","cells":["B2","B3"]},"patch":{"number_format":"$#,##0.00","alignment":{"horizontal":"right"}},"op_mode":"merge"}]}

write batch formula-pattern payloads (`@formula_ops.json`)

Minimal: {"ops":[{"sheet_name":"Sheet1","target_range":"C2:C4","anchor_cell":"C2","base_formula":"B2*2"}]}
Advanced: {"ops":[{"sheet_name":"Sheet1","target_range":"C2:E4","anchor_cell":"C2","base_formula":"B2*2","fill_direction":"both","relative_mode":"excel"}]}
relative_mode valid values: excel, abs_cols, abs_rows

structure-batch payloads (`@structure_ops.json`)

Minimal: {"ops":[{"kind":"rename_sheet","old_name":"Summary","new_name":"Dashboard"}]}
Advanced: {"ops":[{"kind":"copy_range","sheet_name":"Sheet1","dest_sheet_name":"Summary","src_range":"A1:C4","dest_anchor":"A1","include_styles":true,"include_formulas":true}]}

column-size-batch payloads (`@column_size_ops.json`)

Minimal (preferred): {"sheet_name":"Sheet1","ops":[{"range":"A:A","size":{"kind":"width","width_chars":12.0}}]}
Advanced (preferred): {"sheet_name":"Sheet1","ops":[{"target":{"kind":"columns","range":"A:C"},"size":{"kind":"auto","min_width_chars":8.0,"max_width_chars":24.0}}]}
Also accepted (harmonized shape): {"ops":[{"sheet_name":"Sheet1","range":"A:A","size":{"kind":"width","width_chars":12.0}}]}

sheet-layout-batch payloads (`@layout_ops.json`)

Minimal: {"ops":[{"kind":"freeze_panes","sheet_name":"Sheet1","freeze_rows":1,"freeze_cols":1}]}
Advanced: {"ops":[{"kind":"set_page_setup","sheet_name":"Sheet1","orientation":"landscape","fit_to_width":1,"fit_to_height":1}]}

rules-batch payloads (`@rules_ops.json`)

Minimal: {"ops":[{"kind":"set_data_validation","sheet_name":"Sheet1","target_range":"B2:B4","validation":{"kind":"list","formula1":"\"A,B,C\""}}]}
Advanced: {"ops":[{"kind":"set_conditional_format","sheet_name":"Sheet1","target_range":"C2:C10","rule":{"kind":"expression","formula":"C2>100"},"style":{"fill_color":"#FFF2CC","bold":true}}]}

write batch formula-pattern clears cached results for touched formula cells; run workbook recalculate to refresh computed values.

Formula parse policy

Formula-aware commands support:

--formula-parse-policy fail|warn|off

fail — abort
warn — continue and attach grouped diagnostics
off — skip silently

This lets agents choose between strictness and progress depending on the workflow.

CLI reference excerpts

read values <file> <sheet> <range> [range...] [--format dense\|json\|values\|csv] [--include-formulas]
read cells <file> <sheet> <target> [target...] [--include-empty]
read page <file> <sheet> --format <full|compact|values_only> [--start-row ROW] [--page-size N]
workbook create <path> [--sheets Inputs,Calc,...] [--overwrite]
analyze find-value <file> <query> [--sheet S] [--mode value\|label] [--label-direction right\|below\|any]
write batch transform <file> --ops @ops.json (--dry-run\|--in-place\|--output PATH)

Formula write-path provenance (`write_path_provenance`)

Formula-writing commands emit optional provenance metadata for troubleshooting:

written_via: write path (edit, transform_batch, apply_formula_pattern)
formula_targets: sheet/cell or sheet/range targets touched by formula writes

Debug compare workflow:

Apply the same formula target via two paths.
Compare write_path_provenance.written_via and formula_targets in responses.
Use inspect-cells plus recalculate to compare resulting behavior.

Financial presentation starter defaults

Keep label columns (often column A) explicitly sized (roughly 24–36 chars) to prevent clipping.
Apply consistent number formats by semantic type:
- Currency: "$"#,##0.00_);[Red]("$"#,##0.00)
- Percent: 0.0%
- Integer/count: #,##0
Apply sheet-layout-batch freeze panes after header layout stabilizes.

JSON output is compact by default; use --quiet to suppress warnings. Global --output-format csv is currently unsupported; use command-specific CSV options like read table --table-format csv.

MCP server quickstart

The MCP surface is the stateful server version of agent-spreadsheet.

Use it when you want:

workbook caching across calls
fork lifecycle instead of stateless file replacement
multi-turn agent workflows
screenshots and richer server-side orchestration

Claude Code / Claude Desktop

Add to ~/.claude.json or project .mcp.json:

{
  "mcpServers": {
    "spreadsheet": {
      "command": "agent-spreadsheet-mcp",
      "args": ["--workspace-root", "/path/to/workbooks", "--transport", "stdio"]
    }
  }
}

Docker

{
  "mcpServers": {
    "spreadsheet": {
      "command": "docker",
      "args": [
        "run", "-i", "--rm",
        "-v", "/path/to/workbooks:/data",
        "ghcr.io/psu3d0/agent-spreadsheet-mcp:latest-full",
        "--transport", "stdio"
      ]
    }
  }
}

:latest is the read-only slim image (write/fork/recalc tools disabled); :latest-full includes the write tools and recalculation (LibreOffice-backed).

HTTP mode

agent-spreadsheet-mcp --workspace-root /path/to/workbooks
# -> http://127.0.0.1:8079  (POST /mcp, and the canonical route under /v1)

The same process also serves a plain canonical HTTP route for programmatic clients that do not speak MCP:

Route	Purpose
`POST /v1/op/{operation}`	Run a canonical operation; the body is the canonical input object, the response is the canonical envelope
`GET /v1/operations`	Runtime-filtered operation discovery for this process
`GET /v1/registry`	Full canonical registry projection plus the error schema
`GET /v1/artifacts/{handle}`	Bytes for an `artifact:sha256:<hex>` handle produced by `screenshot_sheet`

curl -sS -X POST http://127.0.0.1:8079/v1/op/list_workbooks -d '{}'

Canonical errors return the canonical error envelope with the status mapped from the error code (400 invalid request, 404 unknown operation / resource, 409 revision conflict, 500 operation failed, 501 capability unavailable). Like /mcp, /v1 has no authentication; the loopback default bind is the security boundary. See docs/architecture/canonical-http-route.md.

Configuration

Every setting is available as a CLI flag (agent-spreadsheet-mcp --help), an environment variable, or a config file key (--config file.yaml). CLI takes precedence over the config file.

Variable	Default	Description
`SPREADSHEET_MCP_WORKSPACE`	`.`	Workspace root containing spreadsheet files
`SPREADSHEET_MCP_WORKBOOK`	none	Lock the server to a single workbook path
`SPREADSHEET_MCP_EXTENSIONS`	`xlsx,xlsm,xls,xlsb`	Comma-separated list of allowed workbook extensions
`SPREADSHEET_MCP_ENABLED_TOOLS`	all tools	Restrict execution to the provided tool names (comma-separated)
`SPREADSHEET_MCP_TRANSPORT`	`http`	Transport to expose (`http` or `stdio`)
`SPREADSHEET_MCP_HTTP_BIND`	`127.0.0.1:8079`	HTTP bind address when using http transport
`SPREADSHEET_MCP_RECALC_ENABLED`	`false`	Enable write/recalc tools (uses the native Formualizer backend by default)
`SPREADSHEET_MCP_RECALC_BACKEND`	`auto`	Recalc backend preference: `auto`, `formualizer`, or `libreoffice`
`SPREADSHEET_MCP_MAX_CONCURRENT_RECALCS`	`2`	Max concurrent LibreOffice instances
`SPREADSHEET_MCP_VBA_ENABLED`	`false`	Enable VBA introspection tools (read-only)
`SPREADSHEET_MCP_ALLOW_OVERWRITE`	`false`	Allow `save_fork` to overwrite original workbook files
`SPREADSHEET_MCP_CACHE_CAPACITY`	`5`	Maximum number of workbooks kept in memory
`SPREADSHEET_MCP_TOOL_TIMEOUT_MS`	`30000`	Tool request timeout in milliseconds
`SPREADSHEET_MCP_MAX_RESPONSE_BYTES`	`1000000`	Max response size in bytes

Setting any of the timeout/limit variables (TOOL_TIMEOUT_MS, MAX_RESPONSE_BYTES, MAX_PAYLOAD_BYTES, MAX_CELLS, MAX_ITEMS) to 0 disables that limit.

MCP tool surface

The default MCP router is generated from the canonical operation registry. A write-capable baseline exposes 27 operations: 17 discovery/read/analysis operations and 10 write/lifecycle operations. Capability-backed deployments can add screenshot_sheet, sheetport_manifest, execute_sheetport, and inspect_vba, for up to 31. Nineteen canonical operations are read-only.

Each tool uses the registry descriptor's closed input schema and returns the canonical schema_version / operation / resource_id / revision_id / data envelope. A revision_id identifies the complete observable resource state, not only workbook cell-content bytes: recalculation, evaluation/provenance state, or lifecycle metadata can advance it without a content edit. Clients must use the revision from the latest response envelope for compare-and-swap, cursor, and freshness decisions rather than computing or retaining a content hash. Static MCP annotations report the descriptor's worst-case risk; descriptions identify action-specific risk. close_workbook is excluded because cache eviction is runtime administration.

For the complete operation list and contracts, see Canonical Operation Surface. To add the legacy 0.13 names for one compatibility window, set SPREADSHEET_MCP_SLIM_SURFACE=false; shared names use their legacy schema and envelope in compatibility mode and are registered only once.

JS SDK

agent-spreadsheet-sdk is the app-facing integration layer — the one surface JS/TS code should target.

It provides generated canonical convenience methods, legacy input aliases, unchanged canonical envelopes, and typed capability errors. The complete 31-operation manifest supplies schemas and methods, while availability always comes from the selected live backend.

Backends are a configuration choice, not separate APIs:

MCP backend — connect to a running agent-spreadsheet-mcp server (shared state, forks, multi-client)
Embedded WASM backend — the engine runs in-process on workbook bytes, no server or filesystem required (browser, Node, serverless). The agent-spreadsheet-wasm crate in this repo is that backend's build artifact; it is an internal dependency of the SDK, not a package you consume directly.

Install:

npm i agent-spreadsheet-sdk

Backend status: MCP backend is stable and negotiates operations through live tool discovery (or an explicit supportedOperations list); the embedded WASM backend derives support from its generated binding's operations() descriptors and is tested against the real wasm-bindgen Node package in CI.

Recalc backends

Formula recalculation is pluggable.

Backend	How	Default	Best for
Formualizer	Native Rust engine	Yes	Fast default recalc with no external dependency
LibreOffice	Headless `soffice`	Docker `:latest-full` / explicit builds	Maximum compatibility and screenshot flows

Feature notes:

recalc-formualizer is enabled by default
recalc-libreoffice is available for LibreOffice-backed builds
read and many write flows still work without recalc; only recalculate itself requires a backend

Docker images

Published at ghcr.io/psu3d0/agent-spreadsheet-mcp:

Image	Size	Recalc	Best for
`latest`	~15 MB	No	Read-only analysis and lightweight agent deployments
`latest-full`	~800 MB	Yes	Write + recalc + screenshots

Examples:

# Read-only
docker run -v /path/to/workbooks:/data -p 8079:8079 ghcr.io/psu3d0/agent-spreadsheet-mcp:latest

# Write + recalc
docker run -v /path/to/workbooks:/data -p 8079:8079 ghcr.io/psu3d0/agent-spreadsheet-mcp:latest-full

Workspace layout

agent-spreadsheet/
├── crates/
│   ├── agent-spreadsheet/        # shared engine + asp / agent-spreadsheet CLI
│   ├── agent-spreadsheet-mcp/        # MCP server adapter
│   └── agent-spreadsheet-wasm/   # experimental WASM-facing wrapper
├── npm/
│   ├── agent-spreadsheet/      # npm CLI wrapper
│   └── agent-spreadsheet-sdk/    # JS SDK
├── docs/                       # architecture and design docs
├── benchmarks/                 # scenario budget regression harnesses
└── .github/workflows/          # CI, release, docker builds

Package roles

Package	Role
`agent-spreadsheet`	shared engine and CLI binaries
`agent-spreadsheet-mcp`	stateful MCP transport + server surface
`agent-spreadsheet-wasm`	WASM-facing byte/session wrapper
`agent-spreadsheet`	npm wrapper for the CLI binary
`agent-spreadsheet-sdk`	JS SDK for MCP/WASM-style integrations

Architecture notes

Architecture Overview

Core ideas:

one semantic core shared across CLI, MCP, session, and WASM-facing work
region detection for structural awareness
token-efficient defaults so agents do not over-read spreadsheets
verification as a first-class feature rather than an afterthought
workflow helpers for the common mutations that spreadsheet agents repeatedly struggle with

Token-efficient workflow reference:

Token Efficiency Workflow

Recommended progression:

discover workbook + sheets
detect regions / table-like structures
inspect only the exact region or cells needed
mutate with dry-run or session staging
recalculate if needed
verify proof and review grouped diffs

Development

# Build everything
cargo build --release

# Run formatting, lint, and tests
cargo fmt --all -- --check
cargo clippy --workspace --all-targets -- -D warnings
cargo test --workspace

Local MCP iteration:

WORKSPACE_ROOT=/path/to/workbooks ./scripts/local-docker-mcp.sh

Or point your MCP client directly at the local binary:

{
  "mcpServers": {
    "spreadsheet": {
      "command": "./target/release/agent-spreadsheet-mcp",
      "args": ["--workspace-root", "/path/to/workbooks", "--transport", "stdio"]
    }
  }
}

CLI package README: npm/agent-spreadsheet
Core crate README: crates/agent-spreadsheet
MCP crate README: crates/agent-spreadsheet-mcp
JS SDK README: npm/agent-spreadsheet-sdk
WASM wrapper README: crates/agent-spreadsheet-wasm
Packaging/versioning notes: docs/PACKAGING.md
Heuristics and region detection: docs/HEURISTICS.md
Recalc architecture: docs/RECALC.md

License

Apache-2.0

Add this server

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Server facts

Tools

Questions

How do I install Spreadsheet Kit MCP?

Does Spreadsheet Kit MCP need an API key?

What transport does Spreadsheet Kit MCP use?

When was Spreadsheet Kit MCP last checked?

Documentation

agent-spreadsheet

What this project is

Powered by Formualizer

Why agents use agent-spreadsheet

Built for tool use, not just humans

Safe mutation, not blind mutation

Spreadsheet-aware, not generic file editing

Good agent ergonomics

What is new / what makes this stack different

Install

Shell installer

npm

cargo-binstall

Cargo

mise

MCP server

Docker

JavaScript SDK

Prebuilt binaries

Start here: the core workflows

1) Orient the workbook before reading cells

2) Inspect exactly what an agent needs

3) Do a safe stateless edit → recalc → proof → diff loop

4) Preview structural risk before mutating the workbook

5) Use workflow helpers instead of reinventing row logic

6) Use a stateful session when the edit story gets complex

7) Turn workbook interfaces into contracts with SheetPort

CLI overview

Preferred command groups

Legacy aliases

Discoverability built into the CLI

Command families

read — extraction and inspection

Why these matter for agents

analyze — search, diagnostics, and impact understanding

Why this matters

write — safe mutations and workflow helpers

Safety model

Formula maintenance

Named range maintenance

workbook — file-level flows

verify — proof, not vibes

Why verification matters

session — event-sourced stateful editing

What sessions give you

Canonical loop

History and branching

sheetport — spreadsheet interfaces as executable contracts

Manifest lifecycle

Bind-check + run

Output contracts for agents

Canonical vs compact shapes

Deterministic pagination loops

sheet-page machine contract

Self-describing payloads

Batch payload examples

transform-batch payloads (@transform_ops.json)

style-batch payloads (@style_ops.json)

write batch formula-pattern payloads (@formula_ops.json)

structure-batch payloads (@structure_ops.json)

column-size-batch payloads (@column_size_ops.json)

sheet-layout-batch payloads (@layout_ops.json)

rules-batch payloads (@rules_ops.json)

Formula parse policy

CLI reference excerpts

Formula write-path provenance (write_path_provenance)

Financial presentation starter defaults

MCP server quickstart

Claude Code / Claude Desktop

Docker

`read` — extraction and inspection

`analyze` — search, diagnostics, and impact understanding

`write` — safe mutations and workflow helpers

`workbook` — file-level flows

`verify` — proof, not vibes

`session` — event-sourced stateful editing

`sheetport` — spreadsheet interfaces as executable contracts

`sheet-page` machine contract

transform-batch payloads (`@transform_ops.json`)

style-batch payloads (`@style_ops.json`)

write batch formula-pattern payloads (`@formula_ops.json`)

structure-batch payloads (`@structure_ops.json`)

column-size-batch payloads (`@column_size_ops.json`)

sheet-layout-batch payloads (`@layout_ops.json`)

rules-batch payloads (`@rules_ops.json`)

Formula write-path provenance (`write_path_provenance`)