# Charts by Szum (remote · szum.io)

Create, inspect, manage, and render charts and data visualizations as SVG/PNG or interactive embeds.

- Trust score: 71/100 (medium)
- Change this week: +5
- Registry status: active
- Liveness: live
- Owner verified: no
- Last scored: 2026-08-03

## Components

- remote · `szum.io`: 71/100 (this document), [markdown](https://verifymcp.io/servers/io-szum-charts/szum.md), [page](https://verifymcp.io/servers/io-szum-charts/szum)

## Channel facts

- Endpoint: `https://szum.io/mcp`
- Transports: `streamable-http`
- Auth: `none`
- Version: `1.2.0`

## Trust breakdown

How this component scores in each security and reliability category. Every signal is checked automatically against the live server, and we only credit what we can confirm. Scores are 0–100 per category. Scoring method: https://verifymcp.io/docs/scoring (what has changed: https://verifymcp.io/docs/scoring/changelog)

Scored 2026-08-03.

- **Endpoint Security**: 63/100
  - The endpoint's TLS certificate is valid, in date, and uses a strong key.
  - Authorisation check failed: no authorisation is required to call this server, and it exposes a tool marked destructive (update_chart).
  - HTTPS is enforced; there's no plaintext access path.
  - The HSTS (Strict-Transport-Security) header is present.
  - DNSSEC check failed: this domain isn't protected by DNSSEC.
- **Transport & Reachability**: 100/100
  - Verified streamable-http transport via a live MCP handshake.
- **Schema Quality & AI Usability**: 82/100
  - 100% of prompts and resources have a non-trivial description (not blank, and not just the item's name).
  - AI-judged instruction clarity (good).
  - Tool/resource definitions use about 1682 tokens (~105/item across 16 items; 13 tools + 3 resources), lean.
  - Usage-examples check failed: none of the tools include examples.
- **Stability & Change Management**: 27/100
  - Stability observed for 8 of 30 days with no destabilising changes; credit accrues until the full window elapses.
- **Tool Coverage**: 100/100
  - 100% of tools have a non-trivial description (not blank, and not just the tool's name).
  - 100% of tool parameters carry a description.
  - Structured output schemas are declared (100% of tools); any adoption earns full credit.
- **Capabilities**: 100/100
  - Implements a supported MCP spec version (2025-11-25); the latest is 2026-07-28.
  - Supports UI / widget rendering.

## Install

### Claude

```bash
claude mcp add --transport http io-szum-charts https://szum.io/mcp
```

### Codex

```toml
[mcp_servers.io-szum-charts]
url = "https://szum.io/mcp"
```

### opencode

```json
{
  "$schema": "https://opencode.ai/config.json",
  "mcp": {
    "io-szum-charts": {
      "type": "remote",
      "url": "https://szum.io/mcp",
      "enabled": true
    }
  }
}
```

### OpenClaw

```bash
openclaw mcp add io-szum-charts --url https://szum.io/mcp --transport streamable-http
```

### Hermes

```yaml
mcp_servers:
  io-szum-charts:
    url: "https://szum.io/mcp"
```

### Other

```json
{
  "mcpServers": {
    "io-szum-charts": {
      "type": "http",
      "url": "https://szum.io/mcp"
    }
  }
}
```

The mcpServers block is a cross-client convention. Remote transports vary, so check your client's docs.

## Changelog

Every change recorded for this component, newest first. Days that predate change tracking, or that we cannot explain, say so: "we were watching and nothing happened" and "we were not watching" are different claims.

### 2026-08-03 (score 71, +1)

- [security] The server rewrote its instructions, which are the text every model session reads
- [security] Tool “validate_chart” rewrote its description, which is the text the model reads

### 2026-08-02 (score 70, +1)

- [security] The server rewrote its instructions, which are the text every model session reads
- [functional improvement] Schema quality: fail → pass
- [cosmetic] “save_chart” reworded the description of “config”
- [cosmetic] “render_chart” reworded the description of “config”
- [cosmetic] “update_chart” reworded the description of “config”
- [cosmetic] “validate_chart” reworded the description of “config”

### 2026-08-01 (score 69, +1)

No change was recorded against any check on this day. Stability & Change Management went from 17 to 20. That category is still filling its 30-day observation window: 5 days of observed history at the previous scan, 6 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-07-31 (score 68, 0)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-30 (score 68, +1)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-28 (score 67, +1)

No change was recorded against any check on this day. Stability & Change Management went from 3 to 7. That category is still filling its 30-day observation window: 1 days of observed history at the previous scan, 2 at this one. The score rises as the window fills, whether or not the server changes.

### 2026-07-27 (score 66, −1)

- [functional] We updated how we score, so this day's move reflects our rubric, not a change to the server

### 2026-07-26 (score 67)

First indexed and scored.

## MCP tools (13)

### `render_chart` (~159 tokens)

Render chart

Use this when the user wants to preview or generate a chart from a Szum config after preflighting a generated or materially changed config with validate_chart. Stores a one-hour preview and returns a public image URL; authenticated calls use the account's render allowance.

Input parameters:

- `config` (string, required): JSON string of a complete chart config. Mark field references must match row keys. Chronological annual values use "YYYY" strings on an explicit UTC scale. Configure axes with top-level x and y; hide…

Output parameters:

- `expiresAt` (string)
- `format` (string)
- `imageUrl` (string)
- `mimeType` (string)
- `title` (string)
- `view` (string)

### `save_chart` (~146 tokens)

Save chart

Use this when the user wants to permanently save and publish a chart from a Szum config. Returns permanent public Image and Embed URLs plus Edit and Studio links; requires authentication and saved-chart storage.

Input parameters:

- `config` (string, required): JSON string of a complete chart config. Mark field references must match row keys. Chronological annual values use "YYYY" strings on an explicit UTC scale. Configure axes with top-level x and y; hide…

Output parameters:

- `editUrl` (string)
- `embedUrl` (string)
- `format` (string)
- `id` (string)
- `imageUrl` (string)
- `manageUrl` (string)
- `mimeType` (string)
- `title` (string)
- `view` (string)

### `list_charts` (~165 tokens)

List charts

Use this when the user wants to find charts in their saved library. Returns paginated metadata and URLs, not chart configs; requires authentication. Draft-only editor charts have publishedAt null, hasDraft true, and sizeBytes 0 because sizeBytes measures only the stored published config, not draft storage.

Input parameters:

- `cursor` (string): Opaque nextCursor from the previous page
- `limit` (integer): Page size; defaults to 100 and has a maximum of 1000
- `q` (string): Case-insensitive title substring search; trimmed and limited to 100 characters
- `sort` (string): Sort by creation time (default), update time, or title A-Z
- `source`: Filter by one or more chart sources; omit to list all

Output parameters:

- `items` (array)
- `nextCursor`: Opaque cursor for the next page, or null on the last page
- `total` (integer): Exact match count, present only for title searches

### `get_chart` (~62 tokens)

Get chart

Use this when the user identifies a saved chart by id and wants to view it or retrieve its metadata and URLs. Displays the published chart when available and does not return its config; requires authentication.

Input parameters:

- `id` (string, required): Opaque 32-character saved-chart id

Output parameters:

- `configUrl` (string): Owner-only chart-config endpoint
- `createdAt` (string): ISO-8601 creation timestamp
- `editUrl` (string)
- `embedUrl` (string): Interactive-embed URL
- `id` (string): Opaque 32-character saved-chart id
- `imageUrl` (string): Rendered-image URL
- `manageUrl` (string)
- `publishedAt`: ISO-8601 publish timestamp, or null when public URLs are dark
- `sizeBytes` (integer): Compressed size of the stored published config, excluding drafts; 0 means no published config has been stored yet
- `source` (string): Chart origin; an open set of string values
- `title` (string): Saved chart title
- `updatedAt` (string): ISO-8601 last-update timestamp
- `view` (string)

### `get_chart_config` (~59 tokens)

Get chart config

Use this when the user identifies a saved chart by id and needs its complete published Szum config for inspection or reuse. Does not return a newer editor draft; requires authentication.

Input parameters:

- `id` (string, required): Opaque 32-character saved-chart id

Output parameters:

- `attribution` (boolean): Show a small "Made with Szum" credit in the bottom-right. Always on for free and keyless renders; Creator and Pro omit it by default and set true to opt in.
- `color`
- `data` (array)
- `footer` (string): Caption below the chart (a source line, methodology note, date). URLs, bare domains, and [label](url) links in it are auto-detected and rendered as inline links on every surface.
- `format` (string)
- `headerAlign` (string)
- `height` (integer)
- `locale` (string): Locale identifier accepted by JavaScript Intl and associated with the chart content, such as en, pl, or zh-Hant.
- `margin` (object)
- `marks` (array)
- `plotHeight` (integer)
- `plotWidth` (integer)
- `scale` (integer)
- `subtitle` (string)
- `theme` (string)
- `themeOverrides` (object)
- `title` (string)
- `version` (string)
- `width` (integer)
- `x` (object)
- `y` (object)

### `get_preview_state` (~64 tokens)

Get chart preview state

Use this when the Szum chart App needs to restore a rendered preview as its current transient or saved view. It is read-only, owner-scoped when authenticated, and hidden from the model.

Input parameters:

- `previewId` (string, required): Opaque 16-character chart-preview id

Output parameters:

- `chart` (object)
- `status` (string)

### `update_chart` (~159 tokens)

Update chart

Use this when the user wants to replace and publish a saved chart's config while keeping its id and URLs. Refuses charts with unpublished editor changes; requires authentication and saved-chart storage.

Input parameters:

- `config` (string, required): JSON string of a complete chart config. Mark field references must match row keys. Chronological annual values use "YYYY" strings on an explicit UTC scale. Configure axes with top-level x and y; hide…
- `id` (string, required): Opaque 32-character saved-chart id

Output parameters:

- `configUrl` (string): Owner-only chart-config endpoint
- `createdAt` (string): ISO-8601 creation timestamp
- `editUrl` (string)
- `embedUrl` (string): Interactive-embed URL
- `id` (string): Opaque 32-character saved-chart id
- `imageUrl` (string): Rendered-image URL
- `manageUrl` (string)
- `publishedAt`: ISO-8601 publish timestamp, or null when public URLs are dark
- `sizeBytes` (integer): Compressed size of the stored published config, excluding drafts; 0 means no published config has been stored yet
- `source` (string): Chart origin; an open set of string values
- `title` (string): Saved chart title
- `updatedAt` (string): ISO-8601 last-update timestamp
- `view` (string)

### `rename_chart` (~71 tokens)

Rename chart

Use this when the user wants to change a saved chart's library title without changing its config, publication state, or public URLs; requires authentication.

Input parameters:

- `id` (string, required): Opaque 32-character saved-chart id
- `title` (string, required): New saved-chart title; trimmed and limited to 200 characters

Output parameters:

- `configUrl` (string): Owner-only chart-config endpoint
- `createdAt` (string): ISO-8601 creation timestamp
- `editUrl` (string)
- `embedUrl` (string): Interactive-embed URL
- `id` (string): Opaque 32-character saved-chart id
- `imageUrl` (string): Rendered-image URL
- `manageUrl` (string)
- `publishedAt`: ISO-8601 publish timestamp, or null when public URLs are dark
- `sizeBytes` (integer): Compressed size of the stored published config, excluding drafts; 0 means no published config has been stored yet
- `source` (string): Chart origin; an open set of string values
- `title` (string): Saved chart title
- `updatedAt` (string): ISO-8601 last-update timestamp
- `view` (string)

### `delete_chart` (~55 tokens)

Delete chart

Use this when the user explicitly wants to permanently delete one saved chart. Deletion cannot be undone, and retrying an already completed deletion succeeds; requires authentication.

Input parameters:

- `id` (string, required): Opaque 32-character saved-chart id

Output parameters:

- `deleted` (boolean)

### `validate_chart` (~185 tokens)

Validate chart config

Use this when a chart config will be rendered, saved, or updated. You MUST call validate_chart with the exact current config before every render_chart, save_chart, or update_chart attempt and again after any change. Fix errors and warnings, then revalidate until none remain. Warnings may proceed only after explicit user approval; suggestions do not block. Read-only, free, and fast.

Input parameters:

- `config` (string, required): JSON string of a complete chart config. Mark field references must match row keys. Chronological annual values use "YYYY" strings on an explicit UTC scale. Configure axes with top-level x and y; hide…

Output parameters:

- `errors` (array)
- `message` (string)
- `valid` (boolean)

### `list_themes` (~32 tokens)

List themes

Use this when choosing a visual theme for a chart. Returns every available theme and guidance on where each works best.

Output parameters:

- `themes` (array)

### `list_marks` (~28 tokens)

List mark types

Use this when choosing or configuring chart mark types. Returns every available mark with its properties and defaults.

Output parameters:

- `marks` (array)
- `shared` (object)

### `get_examples` (~49 tokens)

Get example charts

Use this when the model needs current, ready-to-use Szum chart configs or preferred semantic patterns. Optionally filters examples by mark type.

Input parameters:

- `mark_type` (string): Filter examples by mark type

Output parameters:

- `examples` (array)

## Diagnostics

Captured diagnostic sections: TLS, DNSSEC, Authorisation, Transports. The full working is on the page: https://verifymcp.io/servers/io-szum-charts/szum#diagnostics

## Score history

- 2026-08-03: 71
- 2026-08-02: 70
- 2026-08-01: 69
- 2026-07-31: 68
- 2026-07-30: 68
- 2026-07-29: 67
- 2026-07-28: 67
- 2026-07-27: 66
- 2026-07-26: 67

## Links

- Remote endpoint: https://szum.io/mcp
- Website: https://szum.io/
- Changelog RSS feed: https://verifymcp.io/servers/io-szum-charts/szum/changelog.xml
- Changelog JSON feed: https://verifymcp.io/servers/io-szum-charts/szum/changelog.json
- HTML version of this page: https://verifymcp.io/servers/io-szum-charts/szum