spring-projects/spring-ai · error · IllegalStateException

Elicitation not supported by the client:

Error message

Elicitation not supported by the client: 

What it means

Thrown by DefaultMcpSyncRequestContext.elicit when the connected MCP client has not declared the elicitation capability (elicitEnabled() is false); the tool asks the client for structured input but the client cannot respond to elicitation requests.

Solutions

1. Check elicitEnabled() before calling elicit()
2. Connect with an MCP client that supports the elicitation capability
3. Redesign the tool to use optional arguments instead of runtime elicitation

When it happens

Trigger: Thrown at mcp/mcp-annotations/src/main/java/org/springframework/ai/mcp/annotation/context/DefaultMcpSyncRequestContext.java:97 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of spring-projects/spring-ai@98a7beda4f (2026-09-11). Data as JSON: /api/errors/36ee07d3ea52a2e8. Report an issue: GitHub.

Appendix: source

Thrown at mcp/mcp-annotations/src/main/java/org/springframework/ai/mcp/annotation/context/DefaultMcpSyncRequestContext.java:97

		if (!this.rootsEnabled()) {
			throw new IllegalStateException("Roots not supported by the client: " + this.exchange.getClientInfo());
		}
		return this.exchange.listRoots();
	}

	// Elicitation

	@Override
	public boolean elicitEnabled() {
		return !(this.exchange.getClientCapabilities() == null
				|| this.exchange.getClientCapabilities().elicitation() == null);
	}

	@Override
	public <T> StructuredElicitResult<T> elicit(Class<T> type) {

		if (!this.elicitEnabled()) {
			throw new IllegalStateException(
					"Elicitation not supported by the client: " + this.exchange.getClientInfo());
		}

		Assert.notNull(type, "Elicitation response type must not be null");

		ElicitResult elicitResult = this.elicitationInternal("Please provide the required information.", type, null);

		if (elicitResult.action() != ElicitResult.Action.ACCEPT) {
			return new StructuredElicitResult<>(elicitResult.action(), null, elicitResult.meta());
		}

		return new StructuredElicitResult<>(elicitResult.action(),
				jsonHelper.convertFromMap(elicitResult.content(), type), elicitResult.meta());
	}

	@Override
	public <T> StructuredElicitResult<T> elicit(ParameterizedTypeReference<T> type) {

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