Add comprehensive image limits test suite for all vision-capable providers

Tests max image count, size, dimensions, and 8k stress test for:
- Anthropic, OpenAI, Gemini, Mistral, OpenRouter, xAI, Groq, zAI

Key finding: Anthropic's 'many images' rule (>20 images = 2000px max)
does NOT cause API errors. 100 x 8k images work fine. Anthropic likely
auto-resizes internally.

Related to #120
This commit is contained in:
Mario Zechner 2025-12-16 22:21:22 +01:00
parent 4b04c87b3d
commit f1df52ccfd

View file

@ -5,26 +5,59 @@
* - Maximum number of images in a context
* - Maximum image size (bytes)
* - Maximum image dimensions
* - Maximum 8k x 8k images (stress test)
*
* ============================================================================
* DISCOVERED LIMITS (Dec 2025):
* ============================================================================
*
* | Provider | Model | Max Images | Max Size | Max Dimension |
* |-------------|--------------------|------------|----------|---------------|
* | Anthropic | claude-3-5-haiku | 100 | 5MB | 8000px |
* | OpenAI | gpt-4o-mini | 500 | 25MB | (untested) |
* | Gemini | gemini-2.5-flash | ~2500 | 40MB | (untested) |
* | Mistral | pixtral-12b | 8 | ~15MB | (untested) |
* | OpenRouter | z-ai/glm-4.5v | ~40* | ~15MB | (untested) |
* | Provider | Model | Max Images | Max Size | Max Dimension | Max 8k Images |
* |-------------|--------------------|------------|----------|---------------|---------------|
* | Anthropic | claude-3-5-haiku | 100 | 5MB | 8000px | 100 |
* | OpenAI | gpt-4o-mini | 500 | 25MB | 20000px | 50 |
* | Gemini | gemini-2.5-flash | ~2000+* | 40MB | 8000px | (untested) |
* | Mistral | pixtral-12b | 8 | ~15MB | 8000px | 8 |
* | OpenRouter | z-ai/glm-4.5v | ~40** | ~10MB | 20000px | 10 |
* | xAI | grok-2-vision | 100 | 25MB | 8000px | 50 |
* | Groq | llama-4-scout-17b | 5 | ~5MB | ~5760px*** | 0**** |
* | zAI | glm-4.5v | 100 | 20MB | 8000px | 50 |
*
* Notes:
* - Anthropic: Also has a "many images" rule where >20 images reduces max
* dimension to 2000px. Total request size capped at 32MB.
* - Anthropic: Docs mention a "many images" rule (>20 images = 2000px max),
* but testing shows 100 x 8k images work fine. Anthropic may auto-resize
* internally. Total request size capped at 32MB.
* - OpenAI: Documented limit is 20MB, but we observed 25MB working.
* - OpenRouter: * Limited by context window (65k tokens), not explicit image limit.
* - Gemini: Very permissive, hits internal errors around 2500-3000 images.
* No dimension limit found up to 20000px.
* - Gemini: * Very permissive on count, hits rate limits before image limits.
* Dimension limit is 8000px (same as Anthropic).
* - Mistral: Very restrictive on image count (only 8 images allowed).
* Dimension limit is 8000px.
* - OpenRouter: ** Limited by context window (65k tokens), not explicit image
* limit. No dimension limit found up to 20000px.
* - xAI: 25MB limit (26214400 bytes exactly). Dimension limit ~8000px.
* - Groq: *** Very restrictive. Max 5 images, ~5MB size, 33177600 pixels max
* (5760x5760). **** 8k images exceed pixel limit so 0 supported.
* - zAI: Permissive, similar to Anthropic limits.
*
* ============================================================================
* PRACTICAL RECOMMENDATIONS FOR CODING AGENTS:
* ============================================================================
*
* Conservative cross-provider safe limits:
* - Max 5 images per request (for Groq compatibility)
* - Max 5MB per image (for Anthropic/Groq)
* - Max 5760px dimension (for Groq pixel limit)
*
* If excluding Groq:
* - Max 8 images per request (for Mistral)
* - Max 5MB per image (for Anthropic)
* - Max 8000px dimension (common limit)
*
* For Anthropic-only (most common case):
* - Max 100 images per request
* - Max 5MB per image
* - Max 8000px dimension
* - Max 32MB total request size
*
* ============================================================================
*/
@ -362,6 +395,30 @@ describe("Image Limits E2E Tests", () => {
console.log(`\n OpenAI max image size: ~${lastSuccess}MB (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(15);
});
it("should find maximum image dimension limit", { timeout: 600000 }, async () => {
const dimensions = [2000, 4000, 8000, 16000, 20000];
let lastSuccess = 0;
let lastError: string | undefined;
for (const dim of dimensions) {
console.log(` Testing dimension: ${dim}x${dim}...`);
const imageBase64 = generateImage(dim, dim, `dim-${dim}.png`);
const result = await testImageDimensions(model, imageBase64);
if (result.success) {
lastSuccess = dim;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 100)}`);
break;
}
}
console.log(`\n OpenAI max dimension: ~${lastSuccess}px (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(2000);
});
});
// -------------------------------------------------------------------------
@ -413,6 +470,30 @@ describe("Image Limits E2E Tests", () => {
console.log(`\n Gemini max image size: ~${lastSuccess}MB (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(20);
});
it("should find maximum image dimension limit", { timeout: 600000 }, async () => {
const dimensions = [2000, 4000, 8000, 16000, 20000];
let lastSuccess = 0;
let lastError: string | undefined;
for (const dim of dimensions) {
console.log(` Testing dimension: ${dim}x${dim}...`);
const imageBase64 = generateImage(dim, dim, `dim-${dim}.png`);
const result = await testImageDimensions(model, imageBase64);
if (result.success) {
lastSuccess = dim;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 100)}`);
break;
}
}
console.log(`\n Gemini max dimension: ~${lastSuccess}px (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(2000);
});
});
// -------------------------------------------------------------------------
@ -458,6 +539,30 @@ describe("Image Limits E2E Tests", () => {
console.log(`\n Mistral max image size: ~${lastSuccess}MB (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(5);
});
it("should find maximum image dimension limit", { timeout: 600000 }, async () => {
const dimensions = [2000, 4000, 8000, 16000, 20000];
let lastSuccess = 0;
let lastError: string | undefined;
for (const dim of dimensions) {
console.log(` Testing dimension: ${dim}x${dim}...`);
const imageBase64 = generateImage(dim, dim, `dim-${dim}.png`);
const result = await testImageDimensions(model, imageBase64);
if (result.success) {
lastSuccess = dim;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 100)}`);
break;
}
}
console.log(`\n Mistral max dimension: ~${lastSuccess}px (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(2000);
});
});
// -------------------------------------------------------------------------
@ -503,5 +608,481 @@ describe("Image Limits E2E Tests", () => {
console.log(`\n OpenRouter max image size: ~${lastSuccess}MB (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(5);
});
it("should find maximum image dimension limit", { timeout: 600000 }, async () => {
const dimensions = [2000, 4000, 8000, 16000, 20000];
let lastSuccess = 0;
let lastError: string | undefined;
for (const dim of dimensions) {
console.log(` Testing dimension: ${dim}x${dim}...`);
const imageBase64 = generateImage(dim, dim, `dim-${dim}.png`);
const result = await testImageDimensions(model, imageBase64);
if (result.success) {
lastSuccess = dim;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 100)}`);
break;
}
}
console.log(`\n OpenRouter max dimension: ~${lastSuccess}px (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(2000);
});
});
// -------------------------------------------------------------------------
// xAI (grok-2-vision)
// -------------------------------------------------------------------------
describe.skipIf(!process.env.XAI_API_KEY)("xAI (grok-2-vision)", () => {
const model = getModel("xai", "grok-2-vision");
it("should accept a small number of images (5)", async () => {
const result = await testImageCount(model, 5, smallImage);
expect(result.success, result.error).toBe(true);
});
it("should find maximum image count limit", { timeout: 600000 }, async () => {
const { limit, lastError } = await findLimit((count) => testImageCount(model, count, smallImage), 10, 100, 10);
console.log(`\n xAI max images: ~${limit} (last error: ${lastError})`);
expect(limit).toBeGreaterThanOrEqual(5);
});
it("should find maximum image size limit", { timeout: 600000 }, async () => {
const MB = 1024 * 1024;
const sizes = [5, 10, 15, 20, 25];
let lastSuccess = 0;
let lastError: string | undefined;
for (const sizeMB of sizes) {
console.log(` Testing size: ${sizeMB}MB...`);
const imageBase64 = generateImageWithSize(sizeMB * MB, `size-${sizeMB}mb.png`);
const result = await testImageSize(model, imageBase64);
if (result.success) {
lastSuccess = sizeMB;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 100)}`);
break;
}
}
console.log(`\n xAI max image size: ~${lastSuccess}MB (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(5);
});
it("should find maximum image dimension limit", { timeout: 600000 }, async () => {
const dimensions = [2000, 4000, 8000, 16000, 20000];
let lastSuccess = 0;
let lastError: string | undefined;
for (const dim of dimensions) {
console.log(` Testing dimension: ${dim}x${dim}...`);
const imageBase64 = generateImage(dim, dim, `dim-${dim}.png`);
const result = await testImageDimensions(model, imageBase64);
if (result.success) {
lastSuccess = dim;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 100)}`);
break;
}
}
console.log(`\n xAI max dimension: ~${lastSuccess}px (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(2000);
});
});
// -------------------------------------------------------------------------
// Groq (llama-4-scout-17b)
// -------------------------------------------------------------------------
describe.skipIf(!process.env.GROQ_API_KEY)("Groq (llama-4-scout-17b)", () => {
const model = getModel("groq", "meta-llama/llama-4-scout-17b-16e-instruct");
it("should accept a small number of images (5)", async () => {
const result = await testImageCount(model, 5, smallImage);
expect(result.success, result.error).toBe(true);
});
it("should find maximum image count limit", { timeout: 600000 }, async () => {
const { limit, lastError } = await findLimit((count) => testImageCount(model, count, smallImage), 5, 50, 5);
console.log(`\n Groq max images: ~${limit} (last error: ${lastError})`);
expect(limit).toBeGreaterThanOrEqual(5);
});
it("should find maximum image size limit", { timeout: 600000 }, async () => {
const MB = 1024 * 1024;
const sizes = [1, 5, 10, 15, 20];
let lastSuccess = 0;
let lastError: string | undefined;
for (const sizeMB of sizes) {
console.log(` Testing size: ${sizeMB}MB...`);
const imageBase64 = generateImageWithSize(sizeMB * MB, `size-${sizeMB}mb.png`);
const result = await testImageSize(model, imageBase64);
if (result.success) {
lastSuccess = sizeMB;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 100)}`);
break;
}
}
console.log(`\n Groq max image size: ~${lastSuccess}MB (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(1);
});
it("should find maximum image dimension limit", { timeout: 600000 }, async () => {
const dimensions = [2000, 4000, 8000, 16000, 20000];
let lastSuccess = 0;
let lastError: string | undefined;
for (const dim of dimensions) {
console.log(` Testing dimension: ${dim}x${dim}...`);
const imageBase64 = generateImage(dim, dim, `dim-${dim}.png`);
const result = await testImageDimensions(model, imageBase64);
if (result.success) {
lastSuccess = dim;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 100)}`);
break;
}
}
console.log(`\n Groq max dimension: ~${lastSuccess}px (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(2000);
});
});
// -------------------------------------------------------------------------
// zAI (glm-4.5v)
// -------------------------------------------------------------------------
describe.skipIf(!process.env.ZAI_API_KEY)("zAI (glm-4.5v)", () => {
const model = getModel("zai", "glm-4.5v");
it("should accept a small number of images (5)", async () => {
const result = await testImageCount(model, 5, smallImage);
expect(result.success, result.error).toBe(true);
});
it("should find maximum image count limit", { timeout: 600000 }, async () => {
const { limit, lastError } = await findLimit((count) => testImageCount(model, count, smallImage), 10, 100, 10);
console.log(`\n zAI max images: ~${limit} (last error: ${lastError})`);
expect(limit).toBeGreaterThanOrEqual(5);
});
it("should find maximum image size limit", { timeout: 600000 }, async () => {
const MB = 1024 * 1024;
const sizes = [5, 10, 15, 20];
let lastSuccess = 0;
let lastError: string | undefined;
for (const sizeMB of sizes) {
console.log(` Testing size: ${sizeMB}MB...`);
const imageBase64 = generateImageWithSize(sizeMB * MB, `size-${sizeMB}mb.png`);
const result = await testImageSize(model, imageBase64);
if (result.success) {
lastSuccess = sizeMB;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 100)}`);
break;
}
}
console.log(`\n zAI max image size: ~${lastSuccess}MB (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(5);
});
it("should find maximum image dimension limit", { timeout: 600000 }, async () => {
const dimensions = [2000, 4000, 8000, 16000, 20000];
let lastSuccess = 0;
let lastError: string | undefined;
for (const dim of dimensions) {
console.log(` Testing dimension: ${dim}x${dim}...`);
const imageBase64 = generateImage(dim, dim, `dim-${dim}.png`);
const result = await testImageDimensions(model, imageBase64);
if (result.success) {
lastSuccess = dim;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 100)}`);
break;
}
}
console.log(`\n zAI max dimension: ~${lastSuccess}px (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(2000);
});
});
// =========================================================================
// MAX 8K IMAGES TEST
// =========================================================================
// Tests how many 8000x8000 images each provider can handle.
// This is important for:
// 1. Reproducing Anthropic's "many images" rule (>20 images = 2000px max)
// 2. Finding practical limits for prompt caching optimization
// =========================================================================
describe("Max 8K Images (large image stress test)", () => {
// Generate a single 8k image to reuse
// Note: solid color compresses well but still has 8000x8000 pixel dimensions
let image8k: string;
beforeAll(() => {
console.log("Generating 8000x8000 test image...");
image8k = generateImage(8000, 8000, "stress-8k.png");
const sizeBytes = Buffer.from(image8k, "base64").length;
console.log(
` 8k image size: ${(sizeBytes / 1024 / 1024).toFixed(2)}MB (compressed, but still 8000x8000 dimensions)`,
);
});
// Anthropic - known to have "many images" rule (>20 images = 2000px max dimension)
// Testing to find actual limit with 8k dimension images
it.skipIf(!process.env.ANTHROPIC_API_KEY)(
"Anthropic: max 8k images before rejection",
{ timeout: 600000 },
async () => {
const model = getModel("anthropic", "claude-3-5-haiku-20241022");
const counts = [5, 10, 15, 20, 21, 25, 30, 40, 50, 60, 80, 100];
let lastSuccess = 0;
let lastError: string | undefined;
for (const count of counts) {
console.log(` Testing ${count} x 8k images...`);
const result = await testImageCount(model, count, image8k);
if (result.success) {
lastSuccess = count;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 150)}`);
break;
}
}
console.log(`\n Anthropic max 8k images: ${lastSuccess} (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(5);
},
);
// OpenAI
it.skipIf(!process.env.OPENAI_API_KEY)(
"OpenAI: max 8k images before rejection",
{ timeout: 600000 },
async () => {
const model = getModel("openai", "gpt-4o-mini");
const counts = [5, 10, 20, 30, 50];
let lastSuccess = 0;
let lastError: string | undefined;
for (const count of counts) {
console.log(` Testing ${count} x 8k images...`);
const result = await testImageCount(model, count, image8k);
if (result.success) {
lastSuccess = count;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 150)}`);
break;
}
}
console.log(`\n OpenAI max 8k images: ${lastSuccess} (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(5);
},
);
// Gemini
it.skipIf(!process.env.GOOGLE_API_KEY)(
"Gemini: max 8k images before rejection",
{ timeout: 600000 },
async () => {
const model = getModel("google", "gemini-2.5-flash");
const counts = [5, 10, 20, 30, 50];
let lastSuccess = 0;
let lastError: string | undefined;
for (const count of counts) {
console.log(` Testing ${count} x 8k images...`);
const result = await testImageCount(model, count, image8k);
if (result.success) {
lastSuccess = count;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 150)}`);
break;
}
}
console.log(`\n Gemini max 8k images: ${lastSuccess} (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(5);
},
);
// Mistral - already very limited (8 images max)
it.skipIf(!process.env.MISTRAL_API_KEY)(
"Mistral: max 8k images before rejection",
{ timeout: 600000 },
async () => {
const model = getModel("mistral", "pixtral-12b");
const counts = [1, 2, 4, 6, 8];
let lastSuccess = 0;
let lastError: string | undefined;
for (const count of counts) {
console.log(` Testing ${count} x 8k images...`);
const result = await testImageCount(model, count, image8k);
if (result.success) {
lastSuccess = count;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 150)}`);
break;
}
}
console.log(`\n Mistral max 8k images: ${lastSuccess} (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(1);
},
);
// xAI
it.skipIf(!process.env.XAI_API_KEY)("xAI: max 8k images before rejection", { timeout: 600000 }, async () => {
const model = getModel("xai", "grok-2-vision");
const counts = [5, 10, 20, 30, 50];
let lastSuccess = 0;
let lastError: string | undefined;
for (const count of counts) {
console.log(` Testing ${count} x 8k images...`);
const result = await testImageCount(model, count, image8k);
if (result.success) {
lastSuccess = count;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 150)}`);
break;
}
}
console.log(`\n xAI max 8k images: ${lastSuccess} (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(5);
});
// Groq - very limited (5 images, ~5760px max)
it.skipIf(!process.env.GROQ_API_KEY)(
"Groq: max 8k images before rejection (expect 0 - exceeds pixel limit)",
{ timeout: 600000 },
async () => {
const model = getModel("groq", "meta-llama/llama-4-scout-17b-16e-instruct");
// 8k images exceed Groq's 33177600 pixel limit, so even 1 should fail
const counts = [1, 2, 3];
let lastSuccess = 0;
let lastError: string | undefined;
for (const count of counts) {
console.log(` Testing ${count} x 8k images...`);
const result = await testImageCount(model, count, image8k);
if (result.success) {
lastSuccess = count;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 150)}`);
break;
}
}
console.log(`\n Groq max 8k images: ${lastSuccess} (last error: ${lastError})`);
// Groq should fail even with 1 image at 8k (64M pixels > 33M limit)
expect(lastSuccess).toBeGreaterThanOrEqual(0);
},
);
// zAI
it.skipIf(!process.env.ZAI_API_KEY)("zAI: max 8k images before rejection", { timeout: 600000 }, async () => {
const model = getModel("zai", "glm-4.5v");
const counts = [5, 10, 20, 30, 50];
let lastSuccess = 0;
let lastError: string | undefined;
for (const count of counts) {
console.log(` Testing ${count} x 8k images...`);
const result = await testImageCount(model, count, image8k);
if (result.success) {
lastSuccess = count;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 150)}`);
break;
}
}
console.log(`\n zAI max 8k images: ${lastSuccess} (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(5);
});
// OpenRouter
it.skipIf(!process.env.OPENROUTER_API_KEY)(
"OpenRouter: max 8k images before rejection",
{ timeout: 600000 },
async () => {
const model = getModel("openrouter", "z-ai/glm-4.5v");
const counts = [1, 2, 3, 5, 10];
let lastSuccess = 0;
let lastError: string | undefined;
for (const count of counts) {
console.log(` Testing ${count} x 8k images...`);
const result = await testImageCount(model, count, image8k);
if (result.success) {
lastSuccess = count;
console.log(` SUCCESS`);
} else {
lastError = result.error;
console.log(` FAILED: ${result.error?.substring(0, 150)}`);
break;
}
}
console.log(`\n OpenRouter max 8k images: ${lastSuccess} (last error: ${lastError})`);
expect(lastSuccess).toBeGreaterThanOrEqual(1);
},
);
});
});