What causes "failed to create observability exporters: %w" in github/github-mcp-server?

Pass a real logger, or slog.New(slog.DiscardHandler) when logs are unwanted

failed to create observability exporters: %w

Error message

failed to create observability exporters: %w

What it means

observability.NewExporters returned an error: it requires a non-nil *slog.Logger and a non-nil metrics.Metrics implementation. In RunHTTPServer both are always constructed (logger above, metrics.NewNoopMetrics()), so this branch is defensive; it becomes reachable in code that embeds or reuses NewExporters with nil arguments.

Source

Thrown at pkg/http/server.go:148

		return fmt.Errorf("failed to parse API host: %w", err)
	}
	hostType, err := utils.ParseHostType(cfg.Host)
	if err != nil {
		return fmt.Errorf("failed to classify API host: %w", err)
	}

	repoAccessOpts := []lockdown.RepoAccessOption{
		lockdown.WithLogger(logger.With("component", "lockdown")),
	}
	if cfg.RepoAccessCacheTTL != nil {
		repoAccessOpts = append(repoAccessOpts, lockdown.WithTTL(*cfg.RepoAccessCacheTTL))
	}

	featureChecker := createHTTPFeatureChecker(cfg.EnabledFeatures, cfg.InsidersMode)

	obs, err := observability.NewExporters(logger, metrics.NewNoopMetrics())
	if err != nil {
		return fmt.Errorf("failed to create observability exporters: %w", err)
	}

	deps := github.NewRequestDeps(
		apiHost,
		cfg.Version,
		cfg.LockdownMode,
		repoAccessOpts,
		t,
		cfg.ContentWindowSize,
		featureChecker,
		obs,
	)

	// Initialize the global tool scope map
	err = initGlobalToolScopeMap(t, hostType)
	if err != nil {
		return fmt.Errorf("failed to initialize tool scope map: %w", err)
	}

View on GitHub (pinned to 0ea1f775a7)

Solutions

Pass a real logger, or slog.New(slog.DiscardHandler) when logs are unwanted
Pass metrics.NewNoopMetrics() when metrics are unwanted
Fail fast on nil observability deps in your own wiring code

Example fix

// before
obs, err := observability.NewExporters(nil, nil)

// after
obs, err := observability.NewExporters(slog.New(slog.DiscardHandler), metrics.NewNoopMetrics())

Defensive patterns

Strategy: validation

Validate before calling

if logger == nil {
	logger = slog.New(slog.DiscardHandler)
}
if m == nil {
	m = metrics.NewNoopMetrics()
}
obs, err := observability.NewExporters(logger, m)

Prevention

Never pass nil logger or metrics to NewExporters
Default to slog discard handler and noop metrics rather than nil
Add nil-argument checks in your own wiring code to fail fast

When it happens

Trigger: Custom integrations calling NewExporters(nil, nil); refactors that make the logger variable conditional and nil on some path.

Common situations: Embedding the server into another binary and skipping logger wiring; copy-pasted startup code that drops the logger argument.

Related errors

AI-assisted analysis of github/github-mcp-server@0ea1f775a7 (2026-08-15). Data as JSON: /api/errors/fb61ec16282fb5bb. Report an issue: GitHub.