Diagnose and fix Mistral AI common errors and exceptions.
Use when encountering Mistral errors, debugging failed requests,
or troubleshooting integration issues.
Trigger with phrases like "mistral error", "fix mistral",
"mistral not working", "debug mistral".
Install with Codex or Claude Copy this prompt, paste it into Codex, Claude, or another assistant, and let it review the skill page and install it for you.
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Diagnose and fix Mistral AI common errors and exceptions.
Use when encountering Mistral errors, debugging failed requests,
or troubleshooting integration issues.
Trigger with phrases like "mistral error", "fix mistral",
"mistral not working", "debug mistral".
allowed-tools
Read, Grep, Bash(curl:*)
version
1.12.0
license
MIT
author
Jeremy Longshore <jeremy@intentsolutions.io>
tags
["saas","mistral","debugging"]
compatibility
Designed for Claude Code, also compatible with Codex and OpenClaw
Mistral AI Common Errors
Overview
Quick reference for diagnosing and fixing Mistral AI API errors. Covers HTTP status codes, SDK-specific issues, streaming failures, and tool calling problems with real solutions.
Prerequisites
Mistral AI SDK installed
MISTRAL_API_KEY configured
Access to application logs
Instructions
Step 1: Quick Diagnostic
set -euo pipefail
# Test API connectivity and auth
curl -s -w "\nHTTP Status: %{http_code}\n" \
-H "Authorization: Bearer ${MISTRAL_API_KEY}" \
https://api.mistral.ai/v1/models | jq '.data[].id' 2>/dev/null || echo"FAILED"# Check envecho"Key set: ${MISTRAL_API_KEY:+yes}"echo"Key length: ${#MISTRAL_API_KEY}"
Step 2: Error Reference
401 Unauthorized
Error: Authentication failed. Invalid API key.
Causes: Key missing, expired, revoked, or wrong workspace.
Fix:
const apiKey = process.env.MISTRAL_API_KEY;
if (!apiKey) thrownewError('MISTRAL_API_KEY is not set');
// Test the keyconst client = newMistral({ apiKey });
try {
await client.models.list();
} catch (e: any) {
(e. === ) {
.();
}
}
if
status
401
console
error
'API key invalid — regenerate at console.mistral.ai'
Verify manually:
set -euo pipefail
curl -H "Authorization: Bearer ${MISTRAL_API_KEY}" https://api.mistral.ai/v1/models
429 Too Many Requests
Error: Rate limit exceeded. Retry-After: 60
Causes: Exceeded RPM (requests/min) or TPM (tokens/min) for your tier.
Fix:
asyncfunction withBackoff<T>(fn: () =>Promise<T>, maxRetries = 5): Promise<T> {
for (let i = 0; i <= maxRetries; i++) {
try {
returnawaitfn();
} catch (error: any) {
if (error.status !== 429 || i === maxRetries) throw error;
const wait = Math.min(2 ** i * 1000, 60_000);
console.warn(`Rate limited, retrying in ${wait}ms...`);
awaitnewPromise(r =>setTimeout(r, wait));
}
}
thrownewError('Max retries exceeded');
}
functionvalidateMessages(messages: any[]): void {
if (!messages?.length) thrownewError('Messages array empty');
const validRoles = ['system', 'user', 'assistant', 'tool'];
for (const msg of messages) {
if (!validRoles.includes(msg.role)) {
thrownewError(`Invalid role: "${msg.role}"`);
}
if (!msg.content && !msg.toolCalls) {
thrownewError(`Message with role "${msg.role}" has no content`);
}
}
}
400 Bad Request — Tool Call Errors
{"message": "tool_call_id is required for tool messages"}
Fix: Every tool result must include the matching toolCallId:
// After receiving tool_calls from the modelfor (const call of response.choices[0].message.toolCalls) {
const result = awaitexecuteFunction(call.function.name, call.function.arguments);
messages.push({
role: 'tool',
name: call.function.name,
content: JSON.stringify(result),
toolCallId: call.id, // REQUIRED — must match call.id
});
}
413 / Context Length Exceeded
Error: Maximum context length exceeded
Fix: Trim conversation history, keeping system message:
functiontrimToFit(messages: any[], maxChars = 100_000): any[] {
const system = messages.find(m => m.role === 'system');
const rest = messages.filter(m => m.role !== 'system');
constkept: any[] = system ? [system] : [];
let chars = system?.content?.length ?? 0;
// Keep most recent messages that fitfor (let i = rest.length - 1; i >= 0; i--) {
const msgChars = JSON.stringify(rest[i]).length;
if (chars + msgChars > maxChars) break;
chars += msgChars;
kept.splice(system ? 1 : 0, 0, rest[i]);
}
return kept;
}
const client = newMistral({
apiKey: process.env.MISTRAL_API_KEY,
timeoutMs: 60_000, // Increase for long completions
});
// For streaming, the timeout applies to initial connection// Individual chunks have no timeout
