iflytek/astron-agent · warning · IOException

exceeds size limit

Error message

 exceeds size limit

What it means

readBounded enforces a hard size cap on HTTP response bodies. Before streaming, it validates the declared Content-Length: if body.contentLength() exceeds the limit it immediately throws "<description> exceeds size limit" without reading the body. This protects the console backend from a malicious or misconfigured server delivering an oversized sandbox response or skill resource.

Solutions

1. Reduce the requested resource/response size (truncate, paginate, or fetch a smaller artifact).
2. If the resource is legitimately needed, raise the maxResourceBytes limit passed to downloadText.
3. Check why the server declares a larger Content-Length than expected — possibly the wrong file is being served.
4. Compress resources server-side so their transferred size fits within the cap.

Example fix

// before
String text = service.downloadText(url, 1024); // resource is 500KB -> rejected before read
// after
long resourceSize = headContentLength(url);
long limit = Math.max(resourceSize + 1, MAX_RESOURCE_BYTES);
String text = service.downloadText(url, limit);

long declared = httpHead(url).headers().get("Content-Length") != null
        ? Long.parseLong(httpHead(url).headers().get("Content-Length")) : -1;
if (declared > maxResourceBytes) {
    throw new IllegalArgumentException("Resource too large: " + declared + " > " + maxResourceBytes);
}

try {
    String content = service.downloadText(url, maxResourceBytes);
} catch (IOException e) {
    if (e.getMessage() != null && e.getMessage().endsWith("exceeds size limit")) {
        // fetch a smaller artifact or raise the configured limit
    }
}

When it happens

Trigger: A sandbox response or skill resource whose declared Content-Length header is larger than maxSandboxResponseBytes / maxResourceBytes when executeSandbox or downloadText calls readBounded.

Common situations: A skill resource file genuinely larger than the configured cap; a compromised/foreign resource server lying about or sending huge Content-Length; a configured limit left at a very small default while real resources grew; sandbox echoing back a much larger payload than submitted.

Understand the failure class

Background: payload too large / request exceeds maximum size: why libraries cap bytes and how to fix oversize payloads — this error's family across 50 libraries.

Related errors

• sandbox-exec failed: HTTP
• Skill resource URL is not allowed
• Skill resource download failed: HTTP
• AUDIO_FILE_SIZE_EXCEEDED
• PARAM_ERROR

AI-assisted analysis of iflytek/astron-agent@5e758547a8 (2026-09-12). Data as JSON: /api/errors/32148bb713410d77. Report an issue: GitHub.

Appendix: source

Thrown at console/backend/hub/src/main/java/com/iflytek/astron/console/hub/service/chat/springai/SkillRuntimeToolService.java:138

                .build();
        try (Response response = client.newCall(request).execute()) {
            if (!response.isSuccessful()) {
                throw new IOException("Skill resource download failed: HTTP " + response.code());
            }
            ResponseBody body = response.body();
            if (body == null) {
                throw new IOException("Skill resource download returned empty body");
            }
            return decodeText(readBounded(body, maxResourceBytes, "Skill resource"), body);
        }
    }

    private byte[] readBounded(ResponseBody body, long limit, String description)
            throws IOException {
        validateLimit(limit, description);
        long contentLength = body.contentLength();
        if (contentLength > limit) {
            throw new IOException(description + " exceeds size limit");
        }
        int readLimit = Math.toIntExact(limit + 1);
        try (InputStream input = body.byteStream()) {
            byte[] bytes = input.readNBytes(readLimit);
            if (bytes.length > limit) {
                throw new IOException(description + " exceeds size limit");
            }
            return bytes;
        }
    }

    private void validateLimit(long limit, String description) throws IOException {
        if (limit < 1 || limit > MAX_CONFIGURABLE_RESPONSE_BYTES) {
            throw new IOException(description + " size limit is invalid");
        }
    }

    private String decodeText(byte[] bytes, ResponseBody body) {

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