## Validation errors

| Code | HTTP | Title | Retryable |
| --- | --- | --- | --- |
| [missing_parameter](https://docs.blockdaemon.com/docs/missing_parameter) | 400 | Missing required parameter | No |
| [invalid_parameter](https://docs.blockdaemon.com/docs/invalid_parameter) | 400 | Invalid parameter value | No |
| [invalid_chain_id](https://docs.blockdaemon.com/docs/invalid_chain_id) | 400 | Invalid chain identifier | No |
| [unsupported_chain](https://docs.blockdaemon.com/docs/unsupported_chain) | 400 | Unsupported chain or network | No |
| [invalid_address](https://docs.blockdaemon.com/docs/invalid_address) | 422 | Invalid address | No |
| [address_checksum_invalid](https://docs.blockdaemon.com/docs/address_checksum_invalid) | 422 | Address checksum invalid | No |
| [insufficient_balance](https://docs.blockdaemon.com/docs/insufficient_balance) | 422 | Insufficient balance | No |
| [gas_estimation_failed](https://docs.blockdaemon.com/docs/gas_estimation_failed) | 400 | Gas estimation failed | No |
| [nonce_too_low](https://docs.blockdaemon.com/docs/nonce_too_low) | 422 | Nonce too low | No |
| [nonce_too_high](https://docs.blockdaemon.com/docs/nonce_too_high) | 422 | Nonce too high | No |

## Authentication & authorization

| Code | HTTP | Title | Retryable |
| --- | --- | --- | --- |
| [authentication_required](https://docs.blockdaemon.com/docs/authentication_required) | 401 | Authentication required | No |
| [invalid_api_key](https://docs.blockdaemon.com/docs/invalid_api_key) | 401 | Invalid API key | No |
| [permission_denied](https://docs.blockdaemon.com/docs/permission_denied) | 403 | Permission denied | No |

## Not found

| Code | HTTP | Title | Retryable |
| --- | --- | --- | --- |
| [block_not_found](https://docs.blockdaemon.com/docs/block_not_found) | 404 | Block not found | No |
| [event_rule_not_found](https://docs.blockdaemon.com/docs/event_rule_not_found) | 404 | Event rule not found | No |
| [event_target_not_found](https://docs.blockdaemon.com/docs/event_target_not_found) | 404 | Event target not found | No |
| [event_variable_not_found](https://docs.blockdaemon.com/docs/event_variable_not_found) | 404 | Event variable not found | No |
| [route_not_found](https://docs.blockdaemon.com/docs/route_not_found) | 404 | Swap route not available | No |
| [swap_not_found](https://docs.blockdaemon.com/docs/swap_not_found) | 404 | Swap not found | No |

## Conflict

| Code | HTTP | Title | Retryable |
| --- | --- | --- | --- |
| [transaction_already_exists](https://docs.blockdaemon.com/docs/transaction_already_exists) | 409 | Transaction already exists | No |

## Rate limiting

| Code | HTTP | Title | Retryable |
| --- | --- | --- | --- |
| [rate_limited](https://docs.blockdaemon.com/docs/rate_limited) | 429 | Rate limit exceeded | Yes |

## Server errors

| Code | HTTP | Title | Retryable |
| --- | --- | --- | --- |
| [internal_error](https://docs.blockdaemon.com/docs/internal_error) | 500 | Internal server error | Yes |
| [service_unavailable](https://docs.blockdaemon.com/docs/service_unavailable) | 503 | Service temporarily unavailable | Yes |
| [bad_gateway](https://docs.blockdaemon.com/docs/bad_gateway) | 502 | Upstream service error | Yes |
| [not_implemented](https://docs.blockdaemon.com/docs/not_implemented) | 501 | Not implemented | No |