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Use content instead of structuredContent in examples

Browse source 
Not all MCP clients support structuredContent in MCP tool results, so
examples now return data as JSON in content and parse it client-side.

Pattern used:
- Server: content: [{ type: "text", text: JSON.stringify(data) }]
- Client: JSON.parse(result.content!.filter(...).map(...).join(""))

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>
This commit is contained in:
Jonathan Hefner 2025-12-05 16:18:02 -06:00
commit 61cd4ed219
2 changed files with 65 additions and 150 deletions
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71
examples/scenario-modeler-server/server.ts
View file

@ -61,13 +61,6 @@ const GetScenarioDataInputSchema = z.object({
),
});
const GetScenarioDataOutputSchema = z.object({
templates: z.array(ScenarioTemplateSchema),
defaultInputs: ScenarioInputsSchema,
customProjections: z.array(MonthlyProjectionSchema).optional(),
customSummary: ScenarioSummarySchema.optional(),
});
// Types derived from schemas
type ScenarioInputs = z.infer<typeof ScenarioInputsSchema>;
type MonthlyProjection = z.infer<typeof MonthlyProjectionSchema>;
@ -247,37 +240,6 @@ const DEFAULT_INPUTS: ScenarioInputs = {
fixedCosts: 30000,
};
// ============================================================================
// Formatters for text output
// ============================================================================
function formatCurrency(value: number): string {
const absValue = Math.abs(value);
const sign = value < 0 ? "-" : "";
if (absValue >= 1_000_000) {
return `${sign}$${(absValue / 1_000_000).toFixed(2)}M`;
}
if (absValue >= 1_000) {
return `${sign}$${(absValue / 1_000).toFixed(1)}K`;
}
return `${sign}$${Math.round(absValue)}`;
}
function formatScenarioSummary(
summary: ScenarioSummary,
label: string,
): string {
return [
`${label}:`,
` Ending MRR: ${formatCurrency(summary.endingMRR)}`,
` ARR: ${formatCurrency(summary.arr)}`,
` Total Revenue: ${formatCurrency(summary.totalRevenue)}`,
` Total Profit: ${formatCurrency(summary.totalProfit)}`,
` MRR Growth: ${summary.mrrGrowthPct.toFixed(1)}%`,
` Break-even: ${summary.breakEvenMonth ? `Month ${summary.breakEvenMonth}` : "Not achieved"}`,
].join("\n");
}
// ============================================================================
// MCP Server
// ============================================================================
@ -298,7 +260,6 @@ const server = new McpServer({
description:
"Returns SaaS scenario templates and optionally computes custom projections for given inputs",
inputSchema: GetScenarioDataInputSchema.shape,
outputSchema: GetScenarioDataOutputSchema.shape,
_meta: { [RESOURCE_URI_META_KEY]: resourceUri },
},
async (args: {
@ -308,28 +269,18 @@ const server = new McpServer({
? calculateScenario(args.customInputs)
: undefined;
const text = [
"SaaS Scenario Modeler",
"=".repeat(40),
"",
"Available Templates:",
...SCENARIO_TEMPLATES.map(
(t) => ` ${t.icon} ${t.name}: ${t.description}`,
),
"",
customScenario
? formatScenarioSummary(customScenario.summary, "Custom Scenario")
: "Use customInputs parameter to compute projections for a specific scenario.",
].join("\n");
return {
content: [{ type: "text", text }],
structuredContent: {
templates: SCENARIO_TEMPLATES,
defaultInputs: DEFAULT_INPUTS,
customProjections: customScenario?.projections,
customSummary: customScenario?.summary,
},
content: [
{
type: "text",
text: JSON.stringify({
templates: SCENARIO_TEMPLATES,
defaultInputs: DEFAULT_INPUTS,
customProjections: customScenario?.projections,
customSummary: customScenario?.summary,
}),
},
],
};
},
);

12
examples/scenario-modeler-server/src/mcp-app.tsx
View file

@ -24,11 +24,15 @@ interface CallToolResultData {
defaultInputs?: ScenarioInputs;
}
/** Extract templates and defaultInputs from tool result structuredContent */
/** Extract templates and defaultInputs from tool result content */
function extractResultData(result: CallToolResult): CallToolResultData {
if (!result.structuredContent) return {};
const { templates, defaultInputs } =
result.structuredContent as CallToolResultData;
const text = result
.content!.filter(
(c): c is { type: "text"; text: string } => c.type === "text",
)
.map((c) => c.text)
.join("");
const { templates, defaultInputs } = JSON.parse(text) as CallToolResultData;
return { templates, defaultInputs };
}