Agent ready go

<!-- Copyright 2025-2026 Richard Shade. Licensed under Apache-2.0. --> <!-- SPDX-License-Identifier: Apache-2.0 -->

Agent-Ready Go

Make Go applications work effectively with AI coding agents by ensuring all tooling produces machine-readable output, errors are structured, and commands run non-interactively by default.

Workflow

Making a Go app agent-ready involves these steps:

1. Audit — identify gaps against the agent-readiness checklist
2. Structured logging — add/configure slog, Zap, ZeroLog, or Logrus with JSON output
3. Machine-readable output — ensure all commands can emit JSON
4. Linting — add .golangci.yml with thorough config
5. Testing — ensure go test -race -count=1 -timeout=5m with coverage thresholds
6. Error handling — structured errors, meaningful exit codes
7. Non-interactive design — --yes/-y flags, env vars over prompts
8. Makefile — standardize build, test, lint, cover targets

For greenfield projects, apply all steps. For existing projects, run the audit first and address only what's missing.

Step 1: Audit

Run this checklist against the project. Address each ❌:

• Structured logger configured (slog / Zap / ZeroLog / Logrus)
• Logger outputs JSON when not a TTY or when LOG_FORMAT=json
• CLI commands support --json or --output json flag
• .golangci.yml exists with a thorough linter set
• go test -race passes
• Primary exported APIs have working ExampleXxx tests in godoc
• Contract/behavioral testing prioritized over arbitrary line coverage
• go vet ./... passes clean
• All errors wrapped with context (fmt.Errorf("...: %w", err))
• Exit codes: 0 = success, non-zero = failure (no panics in CLI entry)
• context.Context threaded through all I/O-bound functions
• Interactive prompts have --yes/-y bypass flag
• Makefile with build, test, lint, cover, ci targets
• Graceful shutdown on SIGTERM/SIGINT (HTTP services)
• Health check endpoints (/healthz, /readyz) for HTTP services
• govulncheck ./... passes clean
• NO_COLOR respected; no ANSI codes in non-TTY output
• Config loaded from env vars with validation at startup

Step 2: Structured Logging

See references/logging.md for setup patterns for slog, Zap, ZeroLog, and Logrus.

Key requirements:

• Use JSON format when !isatty(os.Stdout.Fd()) or LOG_FORMAT=json
• Include fields: level, ts, msg, plus context fields
• Never use fmt.Println for operational log output
• Log to stderr; keep stdout clean for machine-readable data

Step 3: Machine-Readable Output

Agents parse stdout to validate results. Every non-trivial command must support JSON output.

var outputJSON bool
cmd.Flags().BoolVar(&outputJSON, "json", false, "output results as JSON")

if outputJSON {
    enc := json.NewEncoder(os.Stdout)
    enc.SetIndent("", "  ")
    _ = enc.Encode(result)
} else {
    fmt.Printf("Created: %s\n", result.Name)
}

Rule: structured data → stdout; progress/human messages → stderr.

fmt.Fprintln(os.Stderr, "Processing...")  // progress to stderr
json.NewEncoder(os.Stdout).Encode(result) // data to stdout

Step 4: Linting

Copy assets/.golangci.yml to the project root, then:

golangci-lint run ./...

Requires golangci-lint v1.59+ (v1.x series).

See references/testing.md for linter explanations and tuning guidance.

Step 5: Testing

See references/testing.md for full testing setup.

go test -race -count=1 -timeout=5m -coverprofile=coverage.out ./...
go tool cover -func=coverage.out | tail -1

Do not enforce arbitrary line coverage percentages in CI (e.g., forcing 80%). Agents and humans both benefit more from high-signal contract tests than from padded unit tests.

Instead, enforce that all primary exported APIs have working ExampleXxx tests:

1. Examples act as compilation-enforced documentation.
2. They prove the API contract works as described.
3. They prevent agents from hallucinating incorrect usage patterns.

Step 6: Error Handling

See references/error-handling.md for structured error patterns and exit code conventions.

Quick rules:

• Always wrap: fmt.Errorf("loading config: %w", err)
• CLI main() catches all errors and exits with appropriate code
• Never call os.Exit deep in business logic — return errors up
• Never panic outside of init() / package-level setup

Step 7: Non-Interactive Design

See references/non-interactive.md for patterns.

Any prompt that blocks agent execution must have a --yes/-y bypass:

if !yes {
    confirmed, _ := promptConfirm("Delete all records?")
    if !confirmed {
        return nil
    }
}
// proceed

Step 8: Makefile

Copy assets/Makefile to the project root. Adjust BINARY_NAME and MAIN_PKG for the project.

Standard targets: make build, make test, make lint, make cover, make ci (runs full pipeline).

Resources

File	Contents
references/logging.md	slog, Zap, ZeroLog, Logrus JSON setup
references/testing.md	Race detector, coverage, golangci-lint tuning
references/error-handling.md	Structured errors, exit codes, context
references/non-interactive.md	--yes flags, env vars, stdin detection
references/services.md	HTTP graceful shutdown, health checks, OTel, request ID
references/config.md	Configuration management, env var parsing, validation
assets/.golangci.yml	Production-ready linter config
assets/Makefile	Standard build/test/lint/cover targets