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.

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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).

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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

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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

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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.

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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.

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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.

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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.

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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:

1. Request page 1 without --start-row.
2. If next_start_row is present, call sheet-page again with --start-row <next_start_row>.
3. 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