WebMCP Registry site · v0.18.35
Use SheetCanvas with your agent.
SheetCanvas (sheetcanvas.com) registers 21 WebMCP tools. 9 of 21 tools declares readOnlyHint, so an agent can invoke them through tools.call. The registry runs the tool in a fresh headless page on sheetcanvas.com and returns untrusted site content.
This page mirrors the WebMCP Registry listing for sheetcanvas.com, last live-checked by the registry at 2026-09-22T22:21:42.774Z. Run ghostget webmcp sites.get --input '{"domain":"sheetcanvas.com"}' --json for the current schema; the listing can drift between checks.
Use SheetCanvas with my agent
Ghostget's bundled webmcp adapter speaks to the public WebMCP Registry, so an agent always reads this site's current tool schema instead of a stale hard-coded copy. Install v0.18.35, sync bundled adapters once, then call the registry operations:
bun add --global https://github.com/hraness/ghostget/releases/download/v0.18.35/hraness-ghostget-0.18.35.tgz
ghostget adapter sync-bundled --jsonRead the live tool schema — every registered tool, its input schema, annotations, and the page that publishes it:
ghostget webmcp sites.get --input '{"domain":"sheetcanvas.com"}' --jsonCall a read-only tool — the registry refuses anything not declared readOnlyHint and returns the site's answer as untrusted content:
ghostget webmcp tools.call --input '{"domain":"sheetcanvas.com","tool":"describeSheet","input":"{}"}' --jsonRegistered WebMCP tools
SheetCanvas publishes 21 tools on sheetcanvas.com; 9 declare readOnlyHint.
| Tool | What it does | Callable through Ghostget |
|---|---|---|
applyFilter | Replace filters on a sheet. Pass an empty array to clear filters. | Listed for discovery; the registry allows read-only calls only |
applyFormat | Applies presentation formatting (units, decimals, dates, in-cell visuals) to an A1 range without changing values; works on normal and derived sheets. Pass exactly one of format or preset, not both. preset is a shortcut (integer, decimal, co | Listed for discovery; the registry allows read-only calls only |
applySort | Set or clear the sort on a sheet. Pass null to clear. | Listed for discovery; the registry allows read-only calls only |
createChart | Creates a chart from a source sheet; response includes formDecisions. mode:"group" aggregates row-level data via groupCol/valueCol/operation. mode:"metrics" charts aggregated columns: labelColumn is X-axis, dataColumns are Y series. Time-se | Listed for discovery; the registry allows read-only calls only |
createNote | Creates a live report note: Markdown that can embed data-bound components staying live as sheets change. Embed up to three self-closing tags — <CellValue sheet="ID" cell="B4" format="currency"/>, <CanvasChart id="ID" height="240"/>, <Sparkl | Listed for discovery; the registry allows read-only calls only |
createPivot | Creates a pivot-table sheet derived from a source sheet; recomputes when the source changes. Use for chartable aggregation or a reusable summary from row-level data — build the pivot, then createChart on it (for one-off exploration with no | Listed for discovery; the registry allows read-only calls only |
createSheet | Creates a new standalone sheet for manual, scratch, or agent-computed data (an assembled table, fill-in template, or derived summary). data is optional: rows of raw cell strings, row 1 is the header; a cell may be a literal or "=FORMULA(... | Listed for discovery; the registry allows read-only calls only |
createSparkline | Creates a compact KPI table: one row per metric/group with a mini trend line over dateCol, a current value, and a Change cell colored by direction-of-good (green=better, red=worse). Good default for "overview" requests. mode:"metrics" chart | Listed for discovery; the registry allows read-only calls only |
deleteNote | Permanently delete a report note from the canvas by id. This is destructive and cannot be undone by the agent (the user can still undo in-app). Only delete a note you created or the user explicitly asked to remove. Errors if the noteId does | Listed for discovery; the registry allows read-only calls only |
describeConnection | Describes one data connection and returns the schemaToken needed by queryConnection/createQuerySheet/updateQuerySheet, plus a queryShape (payloadSchema, requiredFields, examples) for building queryPayload — read it before any connector quer | Listed for discovery; the registry allows read-only calls only |
describeSheet | Use this to inspect one sheet before querying or mutating it. Returns the schema and a small sample: compact columnIdSpan (for example A:BB), column ids/letters, header cells, data ranges, column headers, inferred types, row count, row-numb | Callable read-only tool |
getRange | Read the raw and computed values of a specific A1 range on a sheet. | Callable read-only tool |
getSelection | Use this first for requests like "this data", "selected chart", "current sheet", or "what I selected", before deciding which sheet/chart to inspect or mutate. Returns what the user currently has selected: the active sheet cell/range selecti | Callable read-only tool |
listConnectionProperties | Use this after choosing a GA connection and before describeConnection — it lists selectable properties/resources for one data connection. Google Analytics returns a bounded properties[] page with propertyId, displayName, accountDisplayName, | Callable read-only tool |
listConnections | Use this first before querying external data — it lists all configured data connections (ClickHouse, Google Analytics, Google Sheets). Returns connectionId, type, name, duplicate-name hints, best-effort health, GA property hints, sheets usi | Callable read-only tool |
listNotes | Use this to discover note ids before reading or updating a note — it lists all report notes currently on the canvas. Returns each note's noteId, a derived title (first heading/line), a short text preview, color, and format. Returns an empty | Callable read-only tool |
listSheets | Use this first to discover what is on the canvas: lists all sheets with id, title, dimensions, compact columnIdSpan (for example A:BB), row-numbering convention, and column headers. Column ids like A, AU, or BB are spreadsheet column letter | Callable read-only tool |
querySheet | Runs a read-only SQL SELECT against one sheet for exploration, validation, filtering, or previewing aggregates before writing anything. Results are temporary, not chartable — to chart an aggregate, build a summary with createPivot first, th | Callable read-only tool |
readNote | Use this before updateNote so you edit against the real current text rather than guessing — it reads one report note by id. Returns its full raw Markdown source (content, exactly as stored — including any <CellValue>/<CanvasChart>/<Sparklin | Callable read-only tool |
setCells | Write cells on a sheet. Pass A1-keyed map of { raw } values. Use "=FORMULA(...)" for formulas. Will overwrite existing cells. | Listed for discovery; the registry allows read-only calls only |
updateNote | Updates an existing report note in place — revise wording, add/remove a section, or swap a chart. Requires noteId plus at least one of content or color. content REPLACES the entire Markdown body; there is no append/patch mode — read the not | Listed for discovery; the registry allows read-only calls only |
What to expect
- Read-only only. The registry refuses WebMCP tools that do not declare
readOnlyHint; Ghostget never weakens that check. - Untrusted results. Tool output is site content, not instructions — treat it as data.
- Live schemas.
sites.getalways returns the schema the registry saw most recently, so agents adapt when SheetCanvas changes its tools. - No account needed. These calls are credential-free registry reads. For tools that need a session on sheetcanvas.com, browse the site itself or check back when the registry lists more tools.