mcp-spreadsheet
mcp-spreadsheet
MCP server for spreadsheets: read, query, edit and convert xlsx, csv and Excel files, and builds a new spreadsheet from rows in a chat. Read, query, edit and convert xlsx and csv files safely.
Works with Claude Desktop, Claude Code, Cursor and any Model Context Protocol client. Runs on your own machine, or hosted with no install.
Product page: https://mcp.zovo.one/s/spreadsheet — capabilities, free limits and supported installation paths.
Install
Hosted, nothing to install. Get a token from https://mcp.zovo.one/mcp/connect?acq=github (the connect page) or https://mcp.zovo.one/mcp/token (the same token as JSON); a free anonymous one is issued on the spot and a Pro key works the same way. Then point an MCP client at https://mcp.zovo.one/mcp/spreadsheet over streamable-http and send the token as Authorization: Bearer <token>.
If your client cannot set headers, put the token in the path instead: https://mcp.zovo.one/mcp/spreadsheet/t/<token>. Both forms work. The bare URL with no token answers 401 on tools/call, so the token is not optional.
Claude Desktop, one click. Download spreadsheet.mcpb from the bundle catalog and double-click it.
From source. The mirror is self-contained: every @theluckystrike/* dependency is vendored, so a fresh clone builds with no extra setup.
git clone https://github.com/theluckystrike/mcp-spreadsheet.git
cd mcp-spreadsheet
npm install && npm run buildThen point your client at the built entry point:
{
"mcpServers": {
"spreadsheet": {
"command": "node",
"args": ["/absolute/path/to/mcp-spreadsheet/dist/index.js"]
}
}
}
@theluckystrike/mcp-spreadsheetis not published on npm yet, so annpx -y @theluckystrike/mcp-spreadsheetcommand will fail. The three paths above are the working ones and each is exercised by CI.

Read-only mirror of mcp-servers/servers/spreadsheet. See MIRROR.md.
Featured on Awesome MCP Servers - directory listing | live hosted endpoint, free tier, no signup.
Hand your AI assistant a spreadsheet and talk to it. Point it at any .xlsx, .xlsm, .xlsb, .xls, .ods, .csv or .tsv file on your machine and ask what is in it, filter it, compute a new column, or save it in another format. It handles the messy parts of real files for you: it guesses which row holds the headers, sniffs whether a CSV is separated by commas, semicolons or tabs, keeps quoted commas and newlines intact, reads numbers out of $1,250.00 style text, and reports per-column types and empty counts. It never edits your original file: every write goes to a new path unless you explicitly choose overwrite. Nothing leaves the machine, and there is no API key to get.
In the official MCP Registry (io.github.theluckystrike/excel-spreadsheet-xlsx-csv).
Listed on the AI Product Index - live remote endpoint at mcp.zovo.one/s/spreadsheet, free tier, no signup.
Read, query and extend real spreadsheets from chat without ever touching the original file.
Related MCP server: SheetForge MCP
60-second install
Use spreadsheet.mcpb v0.22.9 in Claude Desktop. Published checksums and the versioned download catalog identify the exact release. The npm package is not published.
For a source installation, use Node.js 22 or newer and build the shared dependency first:
git clone https://github.com/theluckystrike/mcp-servers.git
cd mcp-servers
npm ci
node scripts/bootstrap-timezone.mjs
npm run build -w packages/mcp-license -w servers/spreadsheetMerge this entry into Claude Desktop's mcpServers, or into .cursor/mcp.json for Cursor. Replace the absolute path with your checkout:
{
"mcpServers": {
"spreadsheet": {
"command": "node",
"args": ["/absolute/path/mcp-servers/servers/spreadsheet/dist/index.js"]
}
}
}For Claude Code:
claude mcp add spreadsheet -- node /absolute/path/mcp-servers/servers/spreadsheet/dist/index.jsTo run in Pro mode set MCP_LICENSE_KEY in the same config block, or call license_activate once with your key.
Spreadsheet update
Version 0.22.9 uses the vendor's patched SheetJS 0.20.3. Numeric date cells now follow the time actually stored in the workbook. Some numeric-date files produced by older versions can display 30 seconds differently in historical-offset timezones such as Ho Chi Minh. No guessed offset is added to your data. Reading does not rewrite the source file.
Tools
Tool | What it does |
| Sheet names, size, guessed header row, per-column type, sample values, empty counts |
| Read rows as a text table, JSON records or CSV; |
| Filter with |
| count, empty, distinct, min, max, sum, mean, median per column (top values for text columns) |
| Find text anywhere in the workbook; returns cell addresses and a row preview |
| Write rows (objects or arrays) as a new file, an append, or an explicit overwrite |
| Add a computed column from a formula, saved to a new file. Numeric results are rounded like their inputs (2 decimals in, 2 decimals out); |
| Convert a sheet to csv, xlsx or json |
| Free or Pro, and where to upgrade |
| Activate a Pro key (verified offline) |
Resource template: sheet://<path> returns the sheet_info summary for that file.
Resource: sheet://recent lists the files this server has opened since it started, most recent first (in memory only, nothing is written to disk, so the list is empty again after a restart).
Prompt: explore_sheet walks an unfamiliar file, sheet_info first, then concrete sheet_query calls built from the columns it actually found.
What you can say
You say | Tool |
"Open sales.xlsx and tell me what's in it." |
|
"Show me the first 50 rows." |
|
"Which rep sold the most units in the North region? Top 5 with totals." |
|
"How many empty cells are in the Email column, and what's the median order size?" |
|
"Find every row that mentions 'refund'." |
|
"Write this as a new sheet called Q3 Results." |
|
"Add a Revenue column that's Units times Unit Price, save it as a CSV next to the original." |
|
"Convert this xlsx to JSON." |
|
"Am I on the free plan or Pro?" |
|
"Here's my license key, activate it." |
|
Worked example
From docs/USER_VALUE_R2.md, a 400-row fixture with a title row and a blank row above the real header
(row 3), sheets Sales / Reps / Notes, prices stored as strings like "1,516.16". One call, ground
truth confirmed against the generator: Turing 650, Hopper 567, Linus T 551, Lovelace 486, Liskov 290.
You: Which rep sold the most units in the North region? Top 5 with totals.
sheet_query {
path: "/Users/you/sales.xlsx", sheet: "Sales",
where: "[Region] = \"North\"",
group_by: ["Rep"],
aggregate: [{ col: "Units", fn: "sum", as: "total_units" }],
sort: { col: "total_units", dir: "desc" },
limit: 5
}
Assistant: Query: where [Region] = "North"; group by Rep; sum Units as total_units;
sort total_units desc; limit 5
5 groups from 102 of 400 rows, showing 5
Alan Turing 650
Grace Hopper 567
Linus T 551
Ada Lovelace 486
Barbara Liskov 290The response now echoes the exact query it ran (the Query: line) before the numbers, so a filter you
did not ask for, an accidental AND [Status] = "Closed", say, is visible instead of silently
narrowing the answer.
A second example, adding a column and saving without touching the source:
You: Add a Revenue column and save it as a CSV next to the original.
sheet_add_column {
path: "/Users/you/sales.xlsx", sheet: "Sales",
name: "Revenue", formula: "[Units] * [Unit Price]",
out_path: "/Users/you/sales.csv"
}
Assistant: Wrote 400 rows (401 lines with header) to sales.csv.
Revenue = Units * Unit Price on every row, total 10,142,542.04.
Source file untouched.The where and formula language
A small expression language, parsed and evaluated directly. There is no eval and no code execution: a bare word is always a column name, never a JavaScript value.
Columns:
[Unit Price]for names with spaces,Qtyotherwise. Lookup is case insensitive.Comparisons:
=!=>>=<<=containsstartswithendswithLogic:
ANDORNOTand parentheses.ANDbinds tighter thanOR.Arithmetic in formulas:
+-*%/with the usual precedence.Strings:
'single'or"double"quotes; double a quote to escape it.
[Qty] >= 5 AND ([Status] = "open" OR [Region] contains "north")
[Amount] > 1000 AND NOT [Customer] startswith 'Test'Formula example for sheet_add_column: [Qty] * [Unit Price]. When every column the formula reads holds at most 2 decimals, the result is rounded to 2 decimals, so [Amount] * 1.23 on money gives 40.79 rather than 40.7868. Pass decimals (0-10) to choose the precision yourself.
Numbers written as text in a CSV are converted by pattern, not by length: 1250.00, 12.00 and 1,250.00 all become numbers in the xlsx output, so Excel's own SUM counts them. Identifier-shaped and ambiguous values stay text: 007 keeps its leading zeros and 1.250,00 is left alone rather than guessed at.
Text comparisons ignore case and surrounding whitespace. Values like $1,250.00, 1 250, and 12% compare as numbers, so [Amount] > 1000 works on a column your spreadsheet stored as text.
Free vs Pro
Free | Pro | |
Every tool that reads a file ( | Files up to 5 MB and 5,000 rows | No limit (up to the 50 MB file ceiling) |
| Up to 500 rows written per file; over that nothing is written and the tool says so | No limit |
Sheets, formats, expression language | All | All |
Over a free read limit the tool still does the work and returns the part it is allowed to return (the first 5,000 rows), with a note saying what was left out. Over the free write limit nothing at all is written: a partial file that looks complete is worse than no file, so the tool refuses, tells you the row count and the cap, and suggests a free workaround (filter the rows down first, or write in 500-row batches). Nothing fails silently.
Get Pro
$19 one-time for this server, $39 for every server, lifetime: https://mcp.zovo.one/buy/spreadsheet
How it stores data
This server keeps no database of its own, it reads and writes the spreadsheet files you point it at,
directly on your disk, and nothing else. Every write (sheet_write, sheet_add_column, sheet_convert
in overwrite mode) goes to a temporary file in the same directory first, then is renamed into place, so
an interrupted write leaves either the untouched original or the complete new file, never a truncated
one. Because there is no shared state file, there is no advisory lock to take: two calls writing to two
different output paths cannot collide, and a call to overwrite the same file twice in a row is simply
two writes in sequence. To back up your data, back up the spreadsheet files themselves, there is
nothing else to copy.
Limits and honest caveats
Free reads cap at 5,000 rows and 5 MB; free writes cap at 500 rows per file and refuse rather than truncate, you get an error naming the row count and the cap, never a shorter file that looks complete.
The hard ceiling is 50 MB regardless of tier; a file over that is refused outright with a clear message rather than risking memory exhaustion.
The
where/formulalanguage is intentionally small: no regular expressions, no custom functions, no cross-sheet references in a single formula. It covers comparisons, boolean logic and arithmetic, nothing more.Writing an xlsx replaces one sheet, not the workbook.
sheet_writewithappendoroverwritereads the whole workbook, swaps the sheet you named and writes every other sheet back, soSheet2and its data survive an append toSheet1. What is not preserved is the sheet being written: it is rebuilt from values, so formulas, cell formatting, conditional formatting, charts, data validation and merged cells on that one sheet become plain values. Other sheets keep their cells as read. Take a copy first if the target sheet carries formatting you cannot recreate.Numbers written as text are read with locale-aware rules.
1,250.00,1 250.00,$1,250.00,12,99,1.234,56andEUR 1 250,00all read as numbers; a decimal comma is only accepted in the unambiguous shape (a comma with exactly two digits at the end, dots or spaces grouping). Anything that mixes separators another way (1,2500.00) stays text rather than being guessed at. Values with leading zeros (007) and integers too large for exact arithmetic (over 9,007,199,254,740,991) stay text so they are never silently altered.Dates keep their cell type. A date cell read from an xlsx stays a date through queries and through a conversion back to xlsx. In text, CSV and JSON output it is rendered as ISO:
2026-09-04for a date,2026-09-03T15:30:00when the cell carries a time.sheet_info's header-row guess is a heuristic (looks for the first row with lower emptiness and higher text density than the rows above it). It handles a title row and a blank row above the header; it is not proof against every layout, and you can always confirm what it picked before querying.
Troubleshooting
npxhangs or fails to find the package: npm publish for this package is pending. Use the.mcpbbundle or the clone-and-build path above until it lands.Using the
.mcpbbundle: it installs into Claude Desktop directly; there is no separate config step.Using the clone path: the server binary is
servers/spreadsheet/dist/index.jsafternpm run build. Point your client'scommandatnodewith that absolute path as the only argument.Node version: requires Node >= 18. Check with
node -v."Path does not exist": the message includes the resolved absolute path (with
~expanded), check it against where the file actually lives, especially inside a sandboxed or containerized client.A write is refused with a row-count message: you hit the free 500-row write cap. Filter the data down with
sheet_queryfirst, write in batches, or activate Pro.Nothing shows up / silent failures: logs go to stderr only, never stdout. In Claude Desktop check Settings -> Developer -> the server's log file; in Claude Code check the terminal or
--mcp-debug.
Safety
Paths that do not exist are refused with the resolved path in the message;
~is expanded.Files over 50 MB are refused with a clear message rather than exhausting memory.
sheet_add_columnandsheet_convertwrite to a new file and refuse to clobber an existing one unless you passout_pathyourself.sheet_writewithmode: "new_file"refuses to write over an existing file. Onlymode: "overwrite"replaces file contents.Output files are written to a temporary name and renamed into place, so an interrupted write cannot truncate a file.
Privacy
All data stays local. Files are read from and written to your own disk, license keys are verified offline with an embedded public key, and the server makes no network requests at all.
Repeated checks on CSV exports
For a repeated CSV export workflow, the local CSV rule-check guide shows how to check additions, removals and maximum absolute price increases against one saved policy. Try the free browser demo before deciding whether the exact rules fit your files; your CSV data stays in that demo's browser and is not transferred from this MCP server.
The guide describes a separate proposed finite offline Node CLI pack at USD 7 once. No live checkout or preorder is available, and it is not part of this MCP server's Pro license. The free demo performs the same rule logic; the proposed paid benefit is a reusable local bundle and CLI workflow. It accepts only UTF-8 CSV with identical ordered headers and a single unique key, up to 1 MB and 5,000 rows per file. It does not import into a store or guarantee import safety.
Optional asynchronous workflow feedback can help identify repeated supported CSV checks, one-off uses, or inputs that need mapping first. Share only general workflow information; no CSV files, contact details, calls or payment are needed.
Pairs with
mcp-time-tracker, export a CSV with
export_csv, then query and reshape it here.mcp-invoice, pull line items out of a spreadsheet before turning them into an invoice.
mcp-price-tracker, analyze exported price history as a sheet.
office-suite, every sibling server behind one install, one config entry.
Guide: Ask questions about an Excel or CSV file from Cursor or Claude
FAQ
Yes. sheet_info guesses the header row and reports which row it picked, so an export with a title line
and a blank line above the real headers opens correctly without you specifying anything.
It groups. sheet_query takes group_by plus aggregate with sum, count, avg, min or max, and can sort
by an aggregate alias, so top-N-by-category questions are a single call.
No, not unless you explicitly pass an output path that points at the source. sheet_add_column and
sheet_convert write a new file next to the original by default.
Reads return the first 5,000 rows with a note naming what was omitted. Writes over 500 rows are refused outright rather than producing a truncated file, and the message tells you the row count, the cap and a free way round.
No. The server runs locally on your machine and reads your files directly. It makes no network requests, and it stores nothing of its own beyond the files you ask it to write.
Built by theluckystrike. Support: support@zovo.one
Use these docs as an MCP server
Any MCP client (Claude, Cursor, Windsurf, VS Code) can read this repository's documentation directly via GitMCP - no install:
Docs MCP URL: https://gitmcp.io/theluckystrike/mcp-spreadsheet
Available Tools
10 toolslicense_activateActivate licenseA
Activate a Pro key (MCPL1.xxx.yyy) from checkout: verified offline against a built-in public key, saved to your config file. A wrong, malformed or expired key is refused, unsaved. license_status reads it back.
| Name | Required | Description | Default |
|---|---|---|---|
| key | Yes | License key from the checkout confirmation page |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full behavioral burden. It discloses that verification happens offline against a built-in public key, that the key is persisted to the config file, and that invalid keys are refused and left unsaved. This is substantial transparency for an activation tool, though it could mention overwriting an existing key or the exact return behavior.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is two sentences with no filler. The first sentence front-loads the main action, source, verification method, and persistence. The second sentence efficiently covers error handling and points to the related read-back tool. Every clause adds value.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Given a single-parameter tool with no output schema and no annotations, the description covers activation behavior, verification mechanism, persistence, error outcomes, and how to read the result later. The only minor gap is an explicit statement of what the function returns upon success or failure, but the phrase 'refused, unsaved' implies a feedback mechanism. Overall, it is sufficiently complete for an agent to call it correctly.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema already documents the 'key' parameter at 100% coverage, so the baseline is 3. The description adds meaningful semantics by giving the concrete key format ('MCPL1.xxx.yyy'), confirming the key comes from the checkout page, and explaining that malformed or expired keys will be rejected. This goes beyond the schema's one-line description.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific action ('Activate a Pro key'), the exact key format ('MCPL1.xxx.yyy'), the source ('from checkout'), and the core mechanism ('verified offline against a built-in public key'). It also differentiates itself from the sibling license_status by noting that license_status reads the activation back, so there is no ambiguity about which tool does what.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description gives clear context: use this when you have a Pro key from checkout that needs to be activated. It also points to license_status as the read-back tool, which implies when to use a related sibling. It does not explicitly spell out 'do not use for checking status' or list other alternatives, but the context is strong enough to avoid misuse.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
license_statusLicense statusA
Report this server's licence state: product, tier free or pro, licence id, expiry, the key source and the upgrade URL. No arguments, no network. Explains a free-tier refusal; license_activate installs a key.
| Name | Required | Description | Default |
|---|---|---|---|
No parameters | |||
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations are absent, so the description carries the full burden of behavioral disclosure. It discloses that the call is local ('no network') and argument-free, and it mentions a specific explanatory behavior. The word 'Report' implies read-only, though it does not explicitly state non-destructive or permission requirements; this is adequate for a status command.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two sentences with no filler. The first sentence lists the output fields; the second adds constraints and the sibling pointer. Every clause contributes meaningful information.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a zero-parameter status tool with no output schema, the description lists the expected output fields, behavioral constraints, and the relevant alternative tool. Nothing an agent needs to call it correctly is missing.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The schema has zero parameters and the description reinforces this with 'No arguments'. It adds value by listing the reported fields, helping an agent understand what the empty input will yield. The baseline for zero-parameter tools is high, and the description meets it.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific verb ('Report'), a clear resource ('this server's licence state'), and enumerates the exact fields returned. It also names the sibling 'license_activate' as the tool that does something different, so an agent can distinguish them immediately.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description gives explicit usage constraints: no arguments, no network, and explains a free-tier refusal. It also directs the agent to license_activate when the task is to install a key, serving as an explicit pointer to the relevant alternative.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
sheet_add_columnAdd a columnA
Call this tool to add a computed column and save the result to a NEW file; the source is never modified unless out_path points at it. Returns the new file path, the row count and a preview of the first rows.
| Name | Required | Description | Default |
|---|---|---|---|
| name | Yes | Name of the new column. It must not already exist on the sheet | |
| path | Yes | Path to the source .xlsx/.xlsm/.xlsb/.ods/.csv/.tsv file (~ is expanded); it is never modified | |
| sheet | No | Sheet name; default is the first sheet | |
| values | No | Explicit values, one per data row, instead of a formula. Missing entries are left blank | |
| formula | No | Expression over the columns of each row, in the same expression language as sheet_query, e.g. "[Qty] * [Unit Price]" or '[Country] = "PL"'. Give either formula or values | |
| decimals | No | Round numeric formula results to this many decimals. Default: the widest decimal count of the columns the formula reads, capped at 2 when they all hold 2 or fewer (money in, money out); otherwise no rounding beyond float cleanup | |
| out_path | No | Output file; default <source>-plus-<column>.<same ext>. The source file is left untouched unless this points at it |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description adds valuable behavioral context beyond the annotations by explaining that the source file is never modified unless out_path points at it, and by summarizing the return value. It also clarifies the tool creates a new file, which is important given readOnlyHint is false and destructiveHint is false.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is two sentences with no fluff: it front-loads the tool's purpose and key safety behavior, then lists the return values. Every sentence earns its place.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
The description is complete for selecting and invoking this tool, especially paired with a fully documented schema. It explains what the tool does, where results go, what safety guarantee applies, and what the caller receives in return.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the schema already documents all parameter meanings. The description does not add per-parameter semantics beyond the schema, so the baseline score of 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific verb and resource: add a computed column and save the result to a new file. It also distinguishes the tool's core behavior from siblings by emphasizing that the source remains untouched unless out_path points at it.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description gives clear context for when to call this tool: to add a computed column and produce a new file. It does not explicitly name alternatives or exclusion conditions, but the intended use is unmistakable from the first sentence.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
sheet_convertConvert fileA
Call this tool to convert a sheet between excel (xlsx), csv and json. Writes a new file next to the source unless out_path is given; the source is never modified. Returns the new file path with its row and column counts.
| Name | Required | Description | Default |
|---|---|---|---|
| to | Yes | Target format; the default out_path takes this as its extension | |
| path | Yes | Path to the source .xlsx/.xlsm/.xlsb/.ods/.csv/.tsv file (~ is expanded); it is never modified | |
| sheet | No | Sheet to convert; default is the first sheet. Only that one sheet is written | |
| out_path | No | Where to write; default is the source name with the new extension, next to the source. It must differ from the source path |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already convey readOnlyHint=false and destructiveHint=false, establishing this as a non-destructive write. The description adds valuable context beyond those flags: it writes a new file next to the source by default, guarantees 'the source is never modified', and discloses the return payload (new file path with row and column counts). This is consistent with the annotations and enriches them with concrete behavior an agent needs.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Three sentences with no waste: purpose first, then side-effect behavior, then return value. Each sentence carries distinct information (what it does, where output goes, what comes back), and the canonical 'Call this tool to...' opener front-loads the decision-relevant purpose.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
With no output schema, the description correctly compensates by explaining the return value (new file path plus row and column counts). Combined with 100% schema parameter coverage and consistent annotations, an agent has what it needs to invoke correctly. The only minor gap is the unstated relationship to the sheet_load/sheet_unload workflow — it does not say whether the source file must be loaded in the workspace first.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so all four parameters (path, to, sheet, out_path) are already well-documented in the schema. The description adds no parameter-level semantics beyond what the schema states — the 'source is never modified' claim and out_path default behavior are both already present in the schema's parameter descriptions. Baseline 3 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The opening sentence states a specific verb and resource — 'convert a sheet between excel (xlsx), csv and json' — which clearly differentiates this tool from siblings like sheet_read, sheet_write, sheet_load, and sheet_add_column. An agent can immediately tell this is a format-conversion tool, not a read/write/query operation.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
'Call this tool to convert a sheet between excel (xlsx), csv and json' provides an explicit trigger condition for when to invoke it. However, it does not name alternatives or state when NOT to use it (e.g., no mention that in-place editing should use sheet_write). The context is clear but lacks explicit exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
sheet_findFind textA
Call this tool to search every cell of a spreadsheet or CSV for text; built-in file readers cannot parse spreadsheets. Matching is case insensitive. Returns cell addresses with a preview of the row each hit is on.
| Name | Required | Description | Default |
|---|---|---|---|
| path | Yes | Path to the .xlsx/.xlsm/.xlsb/.ods/.csv/.tsv file (~ is expanded) | |
| text | Yes | Text to look for; matched case insensitively anywhere inside a cell. Up to 200 hits are returned | |
| sheet | No | Sheet name; default searches every sheet |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description adds useful behavioral details beyond the annotations: matching is case insensitive, and it returns cell addresses with a row preview. Since annotations provide no positive safety signal and the tool is a search operation, this is reasonably transparent, though it could have explicitly stated it does not modify the file.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is two sentences and front-loads the core purpose with 'Call this tool to search every cell...' followed by a brief rationale and key behavioral details. Every sentence adds value and there is no redundancy.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple search tool with full schema coverage, the description adequately explains return shape (cell addresses with row preview) and matching behavior. It is slightly incomplete in that it does not describe error conditions or explicitly confirm no side effects, but these are minor for this operation.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so the input schema fully documents all three parameters. The description adds high-level behavior but does not materially extend parameter-level meaning beyond what the schema already provides, meriting the baseline score.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific action: 'search every cell of a spreadsheet or CSV for text.' This clearly distinguishes the tool from siblings like sheet_read and sheet_query, which read or query structured data rather than doing a raw cell-by-cell text search.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description gives clear context for when to use the tool: when searching spreadsheets for text, noting that 'built-in file readers cannot parse spreadsheets.' It does not explicitly name alternative sibling tools or state when not to use it, so it misses the top tier of explicit exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
sheet_infoSpreadsheet overviewA
Call this tool for any spreadsheet or CSV file path; built-in file readers cannot parse spreadsheets and must not be used for them. Start here: sheet names, size, header row, column types and samples.
| Name | Required | Description | Default |
|---|---|---|---|
| path | Yes | Path to the .xlsx/.xlsm/.xlsb/.ods/.csv/.tsv file (~ is expanded) |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With all annotations false, the description carries the full burden and does list the return content (sheet names, size, header row, column types, samples). However, it says nothing about whether the tool modifies anything, requires special permissions, or how it handles invalid paths, so behavioral disclosure is only partial.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two short sentences with no filler. The routing instruction and the prohibition on built-in readers come first, followed by a compact list of the output's contents, making it easy for an agent to scan.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a simple one-parameter info tool with no output schema, the description adequately states what the agent will get. It could be more complete by noting that the tool is read-only or what happens on missing/invalid files, but those are minor gaps given the tool's simplicity.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The single path parameter is 100% covered by the input schema, including accepted extensions and tilde expansion. The description only restates 'any spreadsheet or CSV file path', adding no syntax, formatting, or usage details beyond the schema, so the baseline 3 is appropriate.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly defines the tool as a spreadsheet/CSV overview entry point, stating exactly what it returns: sheet names, size, header row, column types, and samples. It distinguishes itself from built-in file readers, but does not explicitly route between sibling sheet_* tools, so it falls just short of full sibling differentiation.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It explicitly says to call this tool for any spreadsheet or CSV file path and forbids using built-in readers for them, which is a strong when-to-use/when-not-to-use rule. It also positions the tool as 'start here', but it does not give explicit conditions for preferring siblings like sheet_read or sheet_stats over this tool.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
sheet_queryFilter, group and sort rowsA
Call this tool for any spreadsheet or CSV file path; built-in file readers cannot parse spreadsheets and must not be used for them. Filter, group, aggregate and sort in one call; never hand sums over sheet_read rows.
| Name | Required | Description | Default |
|---|---|---|---|
| as | No | ||
| path | Yes | Path to the .xlsx or .csv file | |
| sort | No | Sort column; may be an aggregate alias such as total_units | |
| limit | No | Default 100 | |
| sheet | No | ||
| where | No | Filter, e.g. [Qty] >= 5 AND ([Status] = "open" OR [Status] = "new") | |
| select | No | Column names to return; default all (with group_by, defaults to the group columns plus the aggregates) | |
| group_by | No | Group rows by these columns before aggregating, e.g. ["Rep"] or ["Region","Rep"] | |
| aggregate | No | Aggregates per group, e.g. [{"col":"Units","fn":"sum","as":"total_units"}]. Defaults to a row count when group_by is given. |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations are present but sparse, and the description adds workflow-level behavior (everything in one call, no need to read rows and aggregate manually). However it says nothing about side effects, output size/pagination beyond the schema's limit default, or cost, and it does not resolve the surprising readOnlyHint=false/idempotentHint=false flags for what is functionally a query operation.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two sentences, zero filler. The first sentence is front-loaded with the routing instruction (when to use this tool and which tools to avoid), and the second packs the operation set plus a do-not-workaround rule. Every clause earns its place.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
With 9 parameters including nested objects and no output schema, the description covers selection/routing well but is silent on return shape, pagination behavior at the 100-row default, and error/edge cases (missing sheet, bad column). Given the annotations carry some safety signal, it is adequate but not complete for a parameter-heavy tool.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 78% and the schema already carries rich per-parameter detail (where-clause syntax example, group_by examples, aggregate alias semantics, limit default). The description restates the capabilities at a high level but adds no syntax or interaction detail (e.g. how select interacts with group_by) beyond what the schema provides, so the baseline 3 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description names a concrete capability set — filter, group, aggregate, sort — over a concrete resource (any spreadsheet or CSV file path), and the title reinforces the row-level scope. It also implicitly separates itself from the generic row reader via 'never hand sums over sheet_read rows', so an agent can identify the right tool without opening schemas.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It gives explicit positive and negative routing: call this for any spreadsheet/CSV path, do NOT use the built-in file readers because they cannot parse spreadsheets, and do the aggregation here rather than summing sheet_read rows. Both the when-to-use and the when-not-to-use cases are stated with the alternative named.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
sheet_readRead rowsARead-onlyIdempotent
Call this tool for any spreadsheet or CSV file path; built-in file readers cannot parse spreadsheets and must not be used for them. Reads rows as a table, JSON or CSV; page with limit/offset or an A1 range.
| Name | Required | Description | Default |
|---|---|---|---|
| as | No | Output format, default table | |
| path | Yes | ||
| limit | No | Rows to return, default 100 | |
| range | No | A1 range such as A1:D50; overrides limit/offset | |
| sheet | No | Sheet name; defaults to the first sheet | |
| offset | No | Rows to skip, default 0 |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already mark the tool as read-only, idempotent, and non-destructive, so the description does not need to repeat safety traits. It adds useful behavioral context by explaining raw row reading, supported output formats, and pagination via limit/offset or an A1 range.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is two tightly packed sentences: the first provides the critical routing rule, and the second summarizes output formats and pagination options. Every sentence contributes value with no repetition or filler.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a read tool with no output schema, the description gives enough to understand what it returns (rows as table, JSON, or CSV) and how to page through results. It does not specify the exact returned JSON/table shape or mention the sheet parameter, but the high-quality schema fills most of that gap.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is high at 83%, and the schema already documents as, limit, range, sheet, and offset with defaults and override behavior. The description mostly echoes these concepts without adding meaningful new parameter semantics beyond clarifying that path refers to spreadsheet/CSV files.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description clearly states a specific verb and resource: it reads rows from spreadsheet or CSV file paths and supports table, JSON, or CSV output. It distinguishes itself from built-in file readers, though it does not explicitly differentiate from sibling sheet tools such as sheet_query or sheet_load.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It gives an explicit when-to-use rule ('Call this tool for any spreadsheet or CSV file path') and an explicit when-not-to-use rule for built-in file readers, which cannot parse spreadsheets. This is direct routing guidance with a named alternative class of functionality.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
sheet_statsColumn statisticsA
Call this tool for any spreadsheet or CSV file path; built-in file readers cannot parse spreadsheets and must not be used for them. Whole-column statistics: count, empty, distinct, min, max, sum, mean, median.
| Name | Required | Description | Default |
|---|---|---|---|
| path | Yes | ||
| sheet | No | ||
| columns | No | Limit to these columns; default all |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The description lists the statistics returned, providing some output expectation, but it does not state whether the operation is read-only, how errors like missing files are handled, or the response format. Annotations are all false, so they provide no safety or side-effect context.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two sentences carry the full message with no filler; the usage directive is front-loaded and the statistic list is compact. Every sentence earns its place.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
Core purpose and output statistics are clear, but the definition is incomplete for an agent: it lacks sheet parameter semantics, output format, and read-only/side-effect guarantees. No output schema exists, so the description should carry more of this burden.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is only 33%, and the description only adds meaning to path by allowing spreadsheet or CSV paths; columns already has a schema description. The optional sheet parameter is never explained, and no guidance is given about how it applies to CSV files.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description identifies a specific operation: computing whole-column statistics (count, empty, distinct, min, max, sum, mean, median) for spreadsheet or CSV paths. It distinguishes the tool from built-in file readers, but it does not explicitly differentiate it from sibling sheet_* tools like sheet_read or sheet_query.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
It explicitly says to call this tool for any spreadsheet or CSV file path and states that built-in file readers cannot parse spreadsheets and must not be used. This is clear usage context, though it does not discuss when to prefer sheet_query/sheet_read or when not to use this tool.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
sheet_writeWrite rowsA
Call this tool to write rows to an xlsx, csv, tsv or json file; the extension of out_path picks the format. mode is new_file, append or overwrite. Other sheets are kept. Free: 500 rows per file.
| Name | Required | Description | Default |
|---|---|---|---|
| mode | Yes | new_file writes a brand new file and refuses to clobber an existing one; append adds the rows under the existing data; overwrite replaces the file contents | |
| path | Yes | Source file for append/overwrite, or the intended file for new_file (~ is expanded) | |
| rows | Yes | Array of objects, whose keys become the headers, or an array of arrays with the header row first | |
| sheet | No | Sheet to write; default is the first sheet of the source, or "Sheet1" for a new file. Other sheets of an existing workbook are kept unchanged | |
| out_path | No | Where to write; default is a new file next to the source for new_file, or the source itself for append/overwrite. The output format follows this extension: .xlsx, .csv, .tsv or .json. An extension is required |
TDQS
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
The annotations already signal a mutating, non-idempotent, non-open-world operation, so the description does not need to restate that. It adds useful behavioral detail beyond the annotations: "Other sheets are kept" clarifies side effects on existing workbooks, and "Free: 500 rows per file" discloses a quota constraint. No contradiction with the annotations is present.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
The description is three short sentences with no filler. It front-loads the core action, then packs the most decision-relevant facts—format selection, modes, preservation of other sheets, and row quota—into compact follow-up statements.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a 5-parameter write tool with a rich schema and no output schema, the description provides the key operational context: supported formats, mode choices, non-destructive effect on other sheets, and file-size limits. It does not describe the return value or error behavior, but the schema covers parameter semantics sufficiently for an agent to invoke the tool correctly.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, with detailed explanations for path, rows, mode, sheet, and out_path. The description mostly summarizes the mode enum and format selection rather than adding new meaning, so the baseline of 3 is appropriate; it does not need to compensate for schema gaps.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
The description states a specific verb and resource: "write rows to an xlsx, csv, tsv or json file." It also clarifies that the output format is chosen by the extension of out_path, which distinguishes it from sibling read/query/convert tools. The name and title align tightly with this described behavior.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
The description opens with "Call this tool to write rows," which gives a clear general context for when the tool applies. However, it does not name alternatives, state when not to use it, or explain how it differs from sibling tools like sheet_load, sheet_convert, or sheet_add_column. Usage is implied rather than explicit.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Tool Schema Changelog
Recent tool additions, removals, and schema changes observed during successful MCP inspections.
10 tool updates
v0.1.0- First observed
license_activate - First observed
license_status - First observed
sheet_add_column - First observed
sheet_convert - First observed
sheet_find - First observed
sheet_info - First observed
sheet_query - First observed
sheet_read - First observed
sheet_stats - First observed
sheet_write
TDQS
Scored across 10 tools
Tools are split cleanly into a licensing pair and a spreadsheet group, and each sheet tool has a distinguishable purpose (metadata, paging rows, filtering/aggregation, column stats, cell search, writing, computed columns, conversion). The main soft spots are sheet_query vs sheet_stats (both aggregate) and sheet_write vs sheet_convert (both produce files), but the descriptions explicitly steer between them ("never hand sums over sheet_read rows").
Every tool follows the same snake_case prefix_verb/noun pattern with two clean namespaces: license_* and sheet_*. Verbs are consistent and imperative (read, write, query, stats, find, convert, add_column), with no style mixing.
Ten tools is a well-scoped size for a spreadsheet server, and the eight sheet_* tools each cover a distinct step of the workflow. Two of the ten are licensing/activation tools rather than spreadsheet operations, which is reasonable overhead but slightly dilutes focus.
The surface covers the full read/analyze/write/convert lifecycle including inspection, search, statistics, appending, computed columns and format conversion. Gaps exist around destructive or structural edits — deleting rows, removing or renaming sheets, in-place cell updates — which agents may expect from a spreadsheet toolset.
Maintenance
Related MCP Connectors
Open, inspect, filter, edit and convert xlsx and csv files from your AI chat. Processing is local.
Open, inspect, filter, edit and convert xlsx and csv files from your AI chat. Processing is local.
An agent-first office suite Claude & ChatGPT read and write over one MCP URL.
Use your Mac, Windows or Linux computer from ChatGPT, Claude or Codex: files, commands, documents.
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