amir20/dozzle · error

failed to parse arguments

Error message

failed to parse arguments: %w

What it means

parseStreamArgs unmarshals the raw JSON arguments of a stream_logs tool call; when json.Unmarshal fails the JSON is wrapped as 'failed to parse arguments'. The cloud tool caller sent a body that is not valid JSON or has wrong types for fetchLogsArgs fields.

Solutions

1. Validate the tool-call arguments are well-formed JSON before sending
2. Ensure all fetchLogsArgs fields have correct JSON types (strings for container_id, level, regex)
3. Check for truncation of long arguments and re-send the complete payload

Example fix

// before
parseStreamArgs(`{container_id: web}`) // invalid JSON
// after
parseStreamArgs(`{"container_id": "web"}`)

if err := json.Valid([]byte(argsJSON)); err != nil { /* fix JSON before calling */ }

resp, err := executeStreamLogs(ctx, deps, argsJSON, send)
if err != nil && strings.Contains(err.Error(), "failed to parse arguments") {
  // log raw argsJSON and re-send sanitized JSON
}

When it happens

Trigger: executeStreamLogs receives argsJSON that json.Unmarshal rejects: malformed JSON syntax, non-string values for string fields, or a non-object payload.

Common situations: LLM emitting truncated or single-quoted JSON in tool arguments; double-encoded JSON strings; missing quotes around keys; wrong types (regex given as object).

Understand the failure class

Background: "failed to unmarshal" / json.Unmarshal errors: why parsing a response into a Go struct fails and how to fix it — this error's family across 23 libraries.

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

Related errors

• failed to parse arguments
• failed to parse arguments
• failed to parse arguments
• notifications are not configured on this host
• failed to parse arguments

AI-assisted analysis of amir20/dozzle@d9463cbe21 (2026-09-07). Data as JSON: /api/errors/6e090a76a06b2142. Report an issue: GitHub.

Appendix: source

Thrown at internal/cloud/tools_stream.go:22

	"context"
	"encoding/json"
	"fmt"
	"regexp"
	"strings"
	"time"

	"github.com/amir20/dozzle/internal/container"
	pb "github.com/amir20/dozzle/proto/cloud"
	"github.com/rs/zerolog/log"
)

// streamSender is a function that sends a ToolResponse to the cloud.
type streamSender func(resp *pb.ToolResponse) error

func parseStreamArgs(argsJSON string) (*fetchLogsArgs, *regexp.Regexp, error) {
	var args fetchLogsArgs
	if err := json.Unmarshal([]byte(argsJSON), &args); err != nil {
		return nil, nil, fmt.Errorf("failed to parse arguments: %w", err)
	}
	if args.ContainerID == "" {
		return nil, nil, fmt.Errorf("container_id is required")
	}

	var re *regexp.Regexp
	if args.Regex != "" {
		var err error
		re, err = regexp.Compile(args.Regex)
		if err != nil {
			return nil, nil, fmt.Errorf("invalid regex pattern: %w", err)
		}
	}
	return &args, re, nil
}

func matchesFilters(event *container.LogEvent, args *fetchLogsArgs, re *regexp.Regexp) (string, bool) {
	if args.Level != "" && !strings.EqualFold(event.Level, args.Level) {

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