diff --git a/lib/LLM_Clients.cpp b/lib/LLM_Clients.cpp
index 112aeef51..54626477c 100644
--- a/lib/LLM_Clients.cpp
+++ b/lib/LLM_Clients.cpp
@@ -563,8 +563,9 @@ std::string LLM_Bridge::call_generic_openai_with_retry(
 {
 	int attempt = 0;
 	int current_backoff_ms = initial_backoff_ms;
+	int limit = (max_retries < 0) ? 0 : max_retries;
 
-	while (attempt <= max_retries) {
+	while (attempt <= limit) {
 		// Call the base function (attempt 0 is the first try)
 		std::string result = call_generic_openai(prompt, model, url, key, req_id);
 
@@ -637,8 +638,9 @@ std::string LLM_Bridge::call_generic_anthropic_with_retry(
 {
 	int attempt = 0;
 	int current_backoff_ms = initial_backoff_ms;
+	int limit = (max_retries < 0) ? 0 : max_retries;
 
-	while (attempt <= max_retries) {
+	while (attempt <= limit) {
 		// Call the base function (attempt 0 is the first try)
 		std::string result = call_generic_anthropic(prompt, model, url, key, req_id);
 
diff --git a/test/tap/tests/ai_error_handling_edge_cases-t.cpp b/test/tap/tests/ai_error_handling_edge_cases-t.cpp
index e00b935bd..d12c1531e 100644
--- a/test/tap/tests/ai_error_handling_edge_cases-t.cpp
+++ b/test/tap/tests/ai_error_handling_edge_cases-t.cpp
@@ -44,6 +44,11 @@ static bool validate_url_format(const char* url) {
 		return false;
 	}
 
+	// Host part should not start with a colon (e.g. http://:8080)
+	if (host_start[3] == ':') {
+		return false;
+	}
+
 	return true;
 }
 
@@ -67,12 +72,12 @@ static bool validate_api_key_format(const char* key, const char* provider_name)
 	}
 
 	// Check for incomplete OpenAI key format
-	if (strncmp(key, "sk-", 3) == 0 && len < 20) {
+	if (strncmp(key, "sk-", 3) == 0 && len < 10) {
 		return false;
 	}
 
 	// Check for incomplete Anthropic key format
-	if (strncmp(key, "sk-ant-", 7) == 0 && len < 25) {
+	if (strncmp(key, "sk-ant-", 7) == 0 && len < 20) {
 		return false;
 	}
 
@@ -84,9 +89,15 @@ static bool validate_numeric_range(const char* value, int min_val, int max_val,
 		return false;
 	}
 
-	int int_val = atoi(value);
+	char* endptr;
+	long long_val = strtol(value, &endptr, 10);
+
+	// Check if the entire string was consumed
+	if (*endptr != '\0') {
+		return false;
+	}
 
-	if (int_val < min_val || int_val > max_val) {
+	if (long_val < min_val || long_val > max_val) {
 		return false;
 	}
 
@@ -286,12 +297,13 @@ void test_general_edge_cases() {
 // ============================================================================
 
 int main() {
-	// Plan: 35 tests total
-	// API key edge cases: 10 tests
-	// URL edge cases: 9 tests
-	// Numeric range edge cases: 8 tests
-	// Provider format edge cases: 8 tests
-	plan(35);
+	// Plan: 47 tests total
+	// API key edge cases: 12 tests
+	// URL edge cases: 10 tests
+	// Numeric range edge cases: 10 tests
+	// Provider format edge cases: 13 tests
+	// General edge cases: 2 tests
+	plan(47);
 
 	test_api_key_edge_cases();
 	test_url_edge_cases();
diff --git a/test/tap/tests/ai_llm_retry_scenarios-t.cpp b/test/tap/tests/ai_llm_retry_scenarios-t.cpp
index 211586e19..ec00ff73e 100644
--- a/test/tap/tests/ai_llm_retry_scenarios-t.cpp
+++ b/test/tap/tests/ai_llm_retry_scenarios-t.cpp
@@ -87,8 +87,9 @@ static std::string mock_llm_call_with_retry(
 
 	int attempt = 0;
 	int current_backoff_ms = initial_backoff_ms;
+	int limit = (max_retries < 0) ? 0 : max_retries;
 
-	while (attempt <= max_retries) {
+	while (attempt <= limit) {
 		// Call the mock function (attempt 0 is the first try)
 		std::string result = mock_llm_call(prompt);
 
@@ -270,6 +271,32 @@ void test_configurable_parameters() {
 
 	// Expected sleep times: 100ms, 150ms = 250ms total
 	ok(total_sleep_time_ms == 250, "Slower multiplier results in different timing pattern");
+
+	// Test with different max_backoff
+	mock_success_on_attempt = -1; // Always fail
+	total_sleep_time_ms = 0;
+	result = mock_llm_call_with_retry(
+		"test prompt",
+		3,      // max_retries
+		100,    // initial_backoff_ms
+		2.0,    // backoff_multiplier
+		200     // max_backoff_ms (very low)
+	);
+	// Expected sleep times: 100ms, 200ms, 200ms = 500ms total
+	ok(total_sleep_time_ms == 500, "Lower max_backoff caps the total sleep time");
+
+	// Test with high initial backoff
+	mock_success_on_attempt = -1; // Always fail
+	total_sleep_time_ms = 0;
+	result = mock_llm_call_with_retry(
+		"test prompt",
+		1,      // max_retries
+		1000,   // initial_backoff_ms
+		2.0,    // backoff_multiplier
+		5000    // max_backoff_ms
+	);
+	// Expected sleep times: 1000ms total
+	ok(total_sleep_time_ms == 1000, "High initial backoff works correctly");
 }
 
 // ============================================================================
@@ -319,6 +346,30 @@ void test_retry_edge_cases() {
 
 	// Expected sleep times: 100ms, 100ms, 100ms = 300ms total
 	ok(total_sleep_time_ms == 300, "Linear backoff (multiplier=1.0) works correctly");
+
+	// Test with zero initial backoff
+	mock_success_on_attempt = -1; // Always fail
+	total_sleep_time_ms = 0;
+	result = mock_llm_call_with_retry(
+		"test prompt",
+		2,      // max_retries
+		0,      // 0ms initial backoff
+		2.0,    // backoff_multiplier
+		1000    // max_backoff_ms
+	);
+	// Expected sleep times: 0ms, 0ms = 0ms total
+	ok(total_sleep_time_ms == 0, "Zero initial backoff works correctly");
+
+	// Test with very large retry limit but early success
+	mock_success_on_attempt = 2; // Success on 2nd try (1st retry)
+	result = mock_llm_call_with_retry(
+		"test prompt",
+		100,    // 100 retries!
+		10,     // 10ms initial backoff
+		2.0,    // backoff_multiplier
+		1000    // max_backoff_ms
+	);
+	ok(mock_call_count == 2, "Early success works even with large retry limit");
 }
 
 // ============================================================================
@@ -332,10 +383,10 @@ int main() {
 	// Plan: 22 tests total
 	// Exponential backoff timing: 2 tests
 	// Retry limit enforcement: 4 tests
-	// Success recovery: 4 tests
+	// Success recovery: 5 tests
 	// Maximum backoff limit: 2 tests
 	// Configurable parameters: 4 tests
-	// Edge cases: 6 tests
+	// Edge cases: 5 tests
 	plan(22);
 
 	test_exponential_backoff_timing();
diff --git a/test/tap/tests/ai_validation-t.cpp b/test/tap/tests/ai_validation-t.cpp
index 40d58c884..7ebe525c5 100644
--- a/test/tap/tests/ai_validation-t.cpp
+++ b/test/tap/tests/ai_validation-t.cpp
@@ -45,6 +45,11 @@ static bool validate_url_format(const char* url) {
 		return false;
 	}
 
+	// Host part should not start with a colon (e.g. http://:8080)
+	if (host_start[3] == ':') {
+		return false;
+	}
+
 	return true;
 }
 
@@ -70,12 +75,12 @@ static bool validate_api_key_format(const char* key, const char* provider_name)
 	}
 
 	// Check for incomplete OpenAI key format
-	if (strncmp(key, "sk-", 3) == 0 && len < 20) {
+	if (strncmp(key, "sk-", 3) == 0 && len < 10) {
 		return false;
 	}
 
 	// Check for incomplete Anthropic key format
-	if (strncmp(key, "sk-ant-", 7) == 0 && len < 25) {
+	if (strncmp(key, "sk-ant-", 7) == 0 && len < 20) {
 		return false;
 	}
 
@@ -89,9 +94,15 @@ static bool validate_numeric_range(const char* value, int min_val, int max_val,
 		return false;
 	}
 
-	int int_val = atoi(value);
+	char* endptr;
+	long long_val = strtol(value, &endptr, 10);
 
-	if (int_val < min_val || int_val > max_val) {
+	// Check if the entire string was consumed
+	if (*endptr != '\0') {
+		return false;
+	}
+
+	if (long_val < min_val || long_val > max_val) {
 		return false;
 	}
 
@@ -167,6 +178,8 @@ void test_api_key_validation() {
 	   "10-character key accepted (minimum)");
 	ok(validate_api_key_format("sk-proj-shortbutlongenough", "openai"),
 	   "sk-proj- prefix key accepted if length is ok");
+	ok(validate_api_key_format("sk-abc-def-ghi-jkl-mno-pqr", "openai"),
+	   "Long OpenAI-like key accepted");
 
 	// Invalid keys - whitespace
 	ok(!validate_api_key_format("sk-1234567890 with space", "openai"),
@@ -217,10 +230,13 @@ void test_numeric_range_validation() {
 	   "Value above maximum rejected");
 	ok(!validate_numeric_range("", 0, 100, "test_var"),
 	   "Empty value rejected");
-	// Note: atoi("abc") returns 0, which is in range [0,100]
-	// This is a known limitation of the validation function
-	ok(validate_numeric_range("abc", 0, 100, "test_var"),
-	   "Non-numeric value accepted (atoi limitation: 'abc' -> 0)");
+	
+	ok(!validate_numeric_range("abc", 0, 100, "test_var"),
+	   "Non-numeric value rejected");
+	
+	ok(!validate_numeric_range("100abc", 0, 100, "test_var"),
+	   "Number followed by characters rejected");
+
 	// But if the range doesn't include 0, it fails correctly
 	ok(!validate_numeric_range("abc", 1, 100, "test_var"),
 	   "Non-numeric value rejected when range starts above 0");
@@ -321,13 +337,13 @@ void test_edge_cases() {
 // ============================================================================
 
 int main() {
-	// Plan: 61 tests total
+	// Plan: 62 tests total
 	// URL validation: 15 tests (9 valid + 6 invalid)
 	// API key validation: 14 tests
 	// Numeric range: 13 tests
 	// Provider name: 8 tests
-	// Edge cases: 11 tests
-	plan(61);
+	// Edge cases: 12 tests
+	plan(62);
 
 	test_url_validation();
 	test_api_key_validation();