alibaba/spring-ai-alibaba · error · IllegalArgumentException

maxContentLength must be positive

Error message

maxContentLength must be positive

What it means

Builder.maxContentLength validates that the configured truncation limit for fetched content is strictly positive; zero or negative values throw IllegalArgumentException. This guards against nonsensical limits that would truncate all content.

Source

Thrown at spring-ai-alibaba-agent-framework/src/main/java/com/alibaba/cloud/ai/graph/agent/tools/WebFetchTool.java:433

		private int maxCacheSize = 100;

		private int maxRetries = 2;

		private String name = "web_fetch";

		private String description = DEFAULT_TOOL_DESCRIPTION;

		private Builder(ChatClient chatClient) {
			if (chatClient == null) {
				throw new IllegalArgumentException("ChatClient must not be null");
			}
			this.chatClient = chatClient;
		}

		public Builder maxContentLength(int maxContentLength) {
			if (maxContentLength <= 0) {
				throw new IllegalArgumentException("maxContentLength must be positive");
			}
			this.maxContentLength = maxContentLength;
			return this;
		}

		public Builder maxCacheSize(int maxCacheSize) {
			if (maxCacheSize <= 0) {
				throw new IllegalArgumentException("maxCacheSize must be positive");
			}
			this.maxCacheSize = maxCacheSize;
			return this;
		}

		public Builder maxRetries(int maxRetries) {
			if (maxRetries < 0) {
				throw new IllegalArgumentException("maxRetries must be non-negative");
			}
			this.maxRetries = maxRetries;

View on GitHub (pinned to f82da0b50f)

Solutions

1. Pass a positive integer, e.g. .maxContentLength(100_000).
2. If loading from configuration, validate the property > 0 before building.
3. Omit the call to keep the library default.
4. Clamp with Math.max(1, configuredValue) if the value is dynamic.

Example fix

// before
.maxContentLength(0)
// after
.maxContentLength(200_000)

int limit = properties.maxContentLength();
if (limit <= 0) {
    throw new IllegalArgumentException("webfetch.max-content-length must be > 0, got " + limit);
}

boolean isValidSize(int v) { return v > 0; }

try {
    builder.maxContentLength(limit);
} catch (IllegalArgumentException e) {
    log.warn("invalid maxContentLength {}, using default", limit);
    builder.maxContentLength(DEFAULT_CONTENT_LENGTH);
}

When it happens

Trigger: Calling .maxContentLength(0) or a negative value on the WebFetchTool Builder.

Common situations: Copy-paste config where the value comes from properties that default to 0; typo like maxContentLength(-1); computing the limit from an empty/unparsed config value.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• At least one fallback model must be specified
• maxAttempts must be greater than or equal to 1
• initialDelay must be greater than or equal to 0.
• maxCachedThreads must be greater than or equal to 0
• '%s' cannot be blank

AI-assisted analysis of alibaba/spring-ai-alibaba@f82da0b50f (2026-09-09). Data as JSON: /api/errors/4f6f6dc336ff4549. Report an issue: GitHub.