mcp-chat-cards

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Create chart card

create_chart_card

Render a bar, line, pie, or donut chart card with legend and collapsible data table to summarize referenced data visually.

Instructions

Render a dynamically generated SVG chart card (bar, line, pie, or donut) with a legend and a collapsible data table. Use for useful graphics summarizing referenced data.

Input Schema

TableJSON Schema

Name	Required	Description
`type`	Yes
`title`	Yes
`labels`	No	X-axis labels (bar/line)
`series`	No	Data series (bar/line)
`values`	No	Slices (pie/donut)
`yLabel`	No
`subtitle`	No
`tutorTerms`	No	Educational tutor terms. The first occurrence of each term in the card's visible prose is underlined; hovering ~1.2s shows the tip and notifies the host so the model can follow up. Terms are matched once per card, longest first, and never inside code samples, tooltips, or another term's tip. Matching is CASE-SENSITIVE, so "PATH" does not attach its tip to a filesystem "path"; set caseInsensitive on a term to match any casing. Term and tip are PLAIN text.
`description`	No
`contextActions`	No	Right-click menu actions the model anticipates being useful. Choosing one sends its prompt to the conversation; use {{selection}} to include the user's selected text.

Output Schema

TableJSON Schema

Name	Required	Description	Default
`card`	Yes
`parts`	Yes	Split state, present on EVERY card result so one completeness check works for all card types. Cards that cannot split always report {current:1,total:1,hasMore:false}; create_markdown_card and create_code_tour_card pack oversized content into parts and can report more. Read hasMore rather than the card title to decide whether content was withheld.

Schema Changelog

Changes observed during successful MCP inspections.

Changed6 schema fields changedv0.1.3-alphaAug 21, 2026

removedInput schema / $schema

Removed value: -"http://json-schema.org/draft-07/schema#"

changedInput schema / properties / tutorTerms / description

Previous value: -"Educational tutor terms. The first occurrence of each term in the card's visible prose is underlined; hovering ~1.2s shows the tip and notifies the host so the model can follow up. Terms are matched once per card, longest first, and never inside code samples, tooltips, or another term's tip. Term and tip are PLAIN text."New value: +"Educational tutor terms. The first occurrence of each term in the card's visible prose is underlined; hovering ~1.2s shows the tip and notifies the host so the model can follow up. Terms are matched once per card, longest first, and never inside code samples, tooltips, or another term's tip. Matching is CASE-SENSITIVE, so \"PATH\" does not attach its tip to a filesystem \"path\"; set caseInsensitive on a term to match any casing. Term and tip are PLAIN text."

addedInput schema / properties / tutorTerms / items / properties / caseInsensitive

Added value: +{
+  "description": "Match the term regardless of letter case (default false)",
+  "type": "boolean"
+}

removedOutput schema / $schema

Removed value: -"http://json-schema.org/draft-07/schema#"

addedOutput schema / properties / parts

Added value: +{
+  "additionalProperties": false,
+  "description": "Split state, present on EVERY card result so one completeness check works for all card types. Cards that cannot split always report {current:1,total:1,hasMore:false}; create_markdown_card and create_code_tour_card pack oversized content into parts and can report more. Read hasMore rather than the card title to decide whether content was withheld.",
+  "properties": {
+    "current": {
+      "description": "Part number this result rendered (1-based)",
+      "type": "number"
+    },
+    "hasMore": {
+      "description": "True when content was withheld; call again with part: current + 1",
+      "type": "boolean"
+    },
+    "total": {
+      "description": "How many parts the content splits into",
+      "type": "number"
+    }
+  },
+  "required": [
+    "current",
+    "total",
+    "hasMore"
+  ],
+  "type": "object"
+}

changedOutput schema / required

Previous value: -[
-  "card"
-]New value: +[
+  "card",
+  "parts"
+]

Changed1 schema field changedv0.1.1-alphaAug 12, 2026

changedInput schema / properties / tutorTerms / description

Previous value: -"Educational tutor terms. Occurrences in the card are underlined; hovering ~1.2s shows the tip and notifies the host so the model can follow up."New value: +"Educational tutor terms. The first occurrence of each term in the card's visible prose is underlined; hovering ~1.2s shows the tip and notifies the host so the model can follow up. Terms are matched once per card, longest first, and never inside code samples, tooltips, or another term's tip. Term and tip are PLAIN text."

First observedv0.0.0-alphaAug 10, 2026

TDQS

A4/5.0

Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the transparency burden. It discloses the output behavior (SVG chart, legend, collapsible data table) but does not explicitly state that this is a mutating operation inserting a card into the host UI, nor any side effects. This is partial transparency, so a middle score is appropriate.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

Two short sentences front-load the action and output, list chart types, and add a use case without repetition or filler. Every phrase earns its place.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a 10-parameter tool with an output schema and no annotations, the description plus the rich schema is nearly sufficient: required inputs are trivial, the data-parameter schemas are described, and the use case is stated. Minor omissions like explicit chart-type selection guidance prevent a 5.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters3/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema description coverage is 50%, so the baseline is 3. The description adds no parameter-level guidance, but the schema already describes labels, series, values, tutorTerms, and contextActions; remaining params like title, type, and subtitle are semantically obvious. The description does not undersell the parameters.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description names a specific action ('Render'), a concrete resource ('SVG chart card'), and enumerates the supported chart types (bar, line, pie, donut). It clearly differentiates this tool from the table, list, and markdown card siblings by focusing on chart rendering with a legend and collapsible data table.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines4/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The sentence 'Use for useful graphics summarizing referenced data' provides a clear, actionable context for when to invoke the tool. It does not explicitly name alternatives or exclusions, but the context is specific enough to route an agent toward this card type over table/list/markdown siblings.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.