spring-projects/spring-ai · error · IllegalArgumentException

textContent and resource cannot be set at the same time

Error message

textContent and resource cannot be set at the same time

What it means

SystemMessage.Builder.build() enforces mutual exclusivity between textContent and resource: you may supply text directly or load it from a resource, never both. Supplying both throws IllegalArgumentException before any message is created.

Solutions

1. Remove either the text(...) or the resource(...) call — keep exactly one
2. If the resource should win, skip setting text; if the text should win, drop the resource call
3. Load the resource yourself with MessageUtils.readResource and pass it via text(...) if you need pre-processing

Example fix

// before
SystemMessage msg = SystemMessage.builder()
    .text("You are helpful").resource(new ClassPathResource("sys.txt")).build();
// after
SystemMessage msg = SystemMessage.builder()
    .resource(new ClassPathResource("sys.txt")).build();

if (StringUtils.hasText(text) && resource != null) {
    throw new IllegalArgumentException("Set either text or resource, not both");
}

try {
    SystemMessage msg = builder.build();
} catch (IllegalArgumentException e) {
    if (e.getMessage().contains("textContent and resource")) { /* rebuild with a single source */ }
    throw e;
}

When it happens

Trigger: Calling SystemMessage.builder().text("...").resource(myResource).build(); i.e. chaining both the text and resource setters on the same builder.

Common situations: Copy-pasting builder code that already sets text then adding a resource-based prompt loader; conditional code paths where both branches accidentally execute.

Related errors

• textContent and resource cannot be set at the same time
• Anthropic Citations API requires all documents to have…
• argumentType is required
• Bean must not be null
• Either outputType or outputJsonSchema must be set.

AI-assisted analysis of spring-projects/spring-ai@98a7beda4f (2026-09-11). Data as JSON: /api/errors/be88c4ee7e7591f6. Report an issue: GitHub.

Appendix: source

Thrown at spring-ai-model/src/main/java/org/springframework/ai/chat/messages/SystemMessage.java:116

		public Builder text(String textContent) {
			this.textContent = textContent;
			return this;
		}

		public Builder text(Resource resource) {
			this.resource = resource;
			return this;
		}

		public Builder metadata(Map<String, Object> metadata) {
			this.metadata = metadata;
			return this;
		}

		public SystemMessage build() {
			if (StringUtils.hasText(this.textContent) && this.resource != null) {
				throw new IllegalArgumentException("textContent and resource cannot be set at the same time");
			}
			else if (this.resource != null) {
				this.textContent = MessageUtils.readResource(this.resource);
			}
			return new SystemMessage(this.textContent, this.metadata);
		}

	}

}

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