spring-projects/spring-ai · error · IllegalStateException

Neither template nor resource is set

Error message

Neither template nor resource is set

What it means

Validation guard in PromptTemplate.Builder.build(): neither a template string nor a template resource was supplied, so there is no prompt content to render and constructing the PromptTemplate would produce a useless object. It is a generic guard over the builder's own state — the faulty input is an empty builder (both this.template and this.resource left null). Fix by calling template(...) or resource(...) before build().

Source

Thrown at spring-ai-model/src/main/java/org/springframework/ai/chat/prompt/PromptTemplate.java:269

		public Builder renderer(TemplateRenderer renderer) {
			Assert.notNull(renderer, "renderer cannot be null");
			this.renderer = renderer;
			return this;
		}

		public PromptTemplate build() {
			if (this.template != null && this.resource != null) {
				throw new IllegalArgumentException("Only one of template or resource can be set");
			}
			else if (this.resource != null) {
				return new PromptTemplate(this.resource, this.variables, this.renderer);
			}
			else if (this.template != null) {
				return new PromptTemplate(this.template, this.variables, this.renderer);
			}
			else {
				throw new IllegalStateException("Neither template nor resource is set");
			}
		}

	}

}

View on GitHub (pinned to 98a7beda4f)

Solutions

1. Call builder.template(...) with the template string
2. Or call builder.resource(...) with a classpath/file Resource

Example fix

// before
PromptTemplate.builder().variables(Map.of("x", 1)).build();
// after
PromptTemplate.builder().template("Hello {x}").variables(Map.of("x", 1)).build();

if (templateText == null && resource == null) throw new IllegalStateException("Provide a template or resource before building PromptTemplate");

try { return builder.build(); } catch (IllegalStateException e) { logger.error("no template source configured", e); throw e; }

When it happens

Trigger: Calling PromptTemplate.builder().build() (or only setting variables/renderer) without calling template(...) or resource(...).

Common situations: Dynamically built templates where a condition skipped setting the source; builder reused after an earlier branch chose neither; configuration-driven code where the template property resolved to null and was silently skipped.

Understand the failure class

Background: "Must pass :limit option" / "Missing required option" — required option errors explained — this error's family across 41 libraries.

Related errors

• Neither template nor resource is set
• Sampling not supported by the client:
• Bean must not be null
• Bean must not be null
• Bean must not be null

AI-assisted analysis of spring-projects/spring-ai@98a7beda4f (2026-09-11). Data as JSON: /api/errors/1e1ca11e652cb365. Report an issue: GitHub.