Module: AgentHarness

Defined in:
lib/agent_harness.rb,
lib/agent_harness/skill.rb,
lib/agent_harness/errors.rb,
lib/agent_harness/skills.rb,
lib/agent_harness/version.rb,
lib/agent_harness/response.rb,
lib/agent_harness/extensions.rb,
lib/agent_harness/mcp_server.rb,
lib/agent_harness/conversation.rb,
lib/agent_harness/providers/pi.rb,
lib/agent_harness/configuration.rb,
lib/agent_harness/token_tracker.rb,
lib/agent_harness/authentication.rb,
lib/agent_harness/error_taxonomy.rb,
lib/agent_harness/providers/base.rb,
lib/agent_harness/text_transport.rb,
lib/agent_harness/providers/aider.rb,
lib/agent_harness/providers/codex.rb,
lib/agent_harness/command_executor.rb,
lib/agent_harness/provider_runtime.rb,
lib/agent_harness/providers/cursor.rb,
lib/agent_harness/providers/gemini.rb,
lib/agent_harness/release_registry.rb,
lib/agent_harness/sub_agent_config.rb,
lib/agent_harness/mcp_config_loader.rb,
lib/agent_harness/providers/adapter.rb,
lib/agent_harness/dependency_updater.rb,
lib/agent_harness/providers/kilocode.rb,
lib/agent_harness/providers/opencode.rb,
lib/agent_harness/providers/registry.rb,
lib/agent_harness/providers/anthropic.rb,
lib/agent_harness/sub_agent_translator.rb,
lib/agent_harness/execution_preparation.rb,
lib/agent_harness/mcp_config_translator.rb,
lib/agent_harness/orchestration/metrics.rb,
lib/agent_harness/provider_health_check.rb,
lib/agent_harness/sub_agent_file_loader.rb,
lib/agent_harness/providers/mistral_vibe.rb,
lib/agent_harness/docker_command_executor.rb,
lib/agent_harness/orchestration/conductor.rb,
lib/agent_harness/providers/github_copilot.rb,
lib/agent_harness/orchestration/rate_limiter.rb,
lib/agent_harness/openai_compatible_transport.rb,
lib/agent_harness/orchestration/health_monitor.rb,
lib/agent_harness/orchestration/circuit_breaker.rb,
lib/agent_harness/providers/token_usage_parsing.rb,
lib/agent_harness/orchestration/provider_manager.rb,
lib/agent_harness/providers/mcp_config_file_support.rb,
lib/agent_harness/providers/rate_limit_reset_parsing.rb

Overview

AgentHarness provides a unified interface for CLI-based AI coding agents.

It offers:

  • Unified interface for multiple AI coding agents (Claude Code, Cursor, Gemini CLI, etc.)

  • Full orchestration layer with provider switching, circuit breakers, and health monitoring

  • Flexible configuration via YAML, Ruby DSL, or environment variables

  • Dynamic provider registration for custom provider support

  • Token usage tracking for cost and limit calculations

Examples:

Basic usage

AgentHarness.send_message("Write a hello world function", provider: :claude)

With configuration

AgentHarness.configure do |config|
  config.logger = Logger.new(STDOUT)
  config.default_provider = :cursor
end

Direct provider access

provider = AgentHarness.provider(:claude)
provider.send_message(prompt: "Hello")

Defined Under Namespace

Modules: Authentication, ErrorTaxonomy, Extensions, McpConfigTranslator, Orchestration, Providers, Skills, SubAgentTranslator Classes: AuthMismatchError, AuthenticationError, CallbackRegistry, CircuitBreakerConfig, CircuitOpenError, CommandExecutionError, CommandExecutor, Configuration, ConfigurationError, Conversation, DependencyUpdater, DockerCommandExecutor, Error, ExecutionPreparation, ExtensionCompatibilityError, HealthCheckConfig, IdleTimeoutError, InvalidDurationError, McpConfigLoader, McpConfigurationError, McpServer, McpTransportUnsupportedError, McpUnsupportedError, NoProvidersAvailableError, OpenAICompatibleTransport, OrchestrationConfig, ProviderConfig, ProviderError, ProviderHealthCheck, ProviderNotFoundError, ProviderRuntime, ProviderUnavailableError, RateLimitConfig, RateLimitError, ReleaseRegistry, Response, RetryConfig, Skill, SubAgentConfig, SubAgentFileLoader, TextTransport, TimeoutError, TokenTracker, ToolDefinition, ToolRegistry, UnsupportedAuthFlowError

Constant Summary collapse

VERSION = 
"0.22.0"

Class Method Summary collapse

Class Method Details

.auth_capabilities(provider_name) ⇒ Hash

Get authentication flow capabilities for a provider

Parameters:

  • provider_name (Symbol) —

    the provider name

Returns:

  • (Hash) —

    capabilities with :auth_type, :auth_url, :refresh keys

Raises:



278
279
280
 
# File 'lib/agent_harness.rb', line 278

def auth_capabilities(provider_name)
  Authentication.auth_capabilities(provider_name)
end

.auth_status(provider_name) ⇒ Hash

Get detailed authentication status for a provider

Parameters:

  • provider_name (Symbol) —

    the provider name

Returns:

  • (Hash) —

    status with :valid, :expires_at, :error keys



270
271
272
 
# File 'lib/agent_harness.rb', line 270

def auth_status(provider_name)
  Authentication.auth_status(provider_name)
end

.auth_url(provider_name) ⇒ String

Generate an OAuth URL for a provider

Parameters:

  • provider_name (Symbol) —

    the provider name

Returns:

  • (String) —

    the OAuth authorization URL

Raises:



294
295
296
 
# File 'lib/agent_harness.rb', line 294

def auth_url(provider_name)
  Authentication.auth_url(provider_name)
end

.auth_url_supported?(provider_name) ⇒ Boolean

Check whether OAuth URL generation is supported for a provider

Parameters:

  • provider_name (Symbol) —

    the provider name

Returns:

  • (Boolean) —

    true if auth_url can be called for the provider

Raises:



286
287
288
 
# File 'lib/agent_harness.rb', line 286

def auth_url_supported?(provider_name)
  Authentication.auth_url_supported?(provider_name)
end

.auth_valid?(provider_name) ⇒ Boolean

Check if authentication is valid for a provider

Parameters:

  • provider_name (Symbol) —

    the provider name

Returns:

  • (Boolean) —

    true if auth is valid



263
264
265
 
# File 'lib/agent_harness.rb', line 263

def auth_valid?(provider_name)
  Authentication.auth_valid?(provider_name)
end

.build_config(name, **options) ⇒ ProviderConfig

Build a new ProviderConfig with defaults for the given provider

Parameters:

  • name (Symbol, String) —

    the provider name

  • options (Hash) —

    optional attribute overrides to merge

Returns:



168
169
170
171
172
 
# File 'lib/agent_harness.rb', line 168

def build_config(name, **options)
  config = ProviderConfig.new(name)
  config.merge!(options) unless options.empty?
  config
end

.check_provider(provider_name, timeout: nil, executor: nil, provider_runtime: nil) ⇒ Hash

Check health of a single provider

Parameters:

  • provider_name (Symbol) —

    the provider name

  • timeout (Integer, nil) (defaults to: nil) —

    timeout in seconds (nil lets ProviderHealthCheck apply its validated default)

Returns:

  • (Hash) —

    health status with :name, :status, :message, :latency_ms



338
339
340
341
342
343
344
 
# File 'lib/agent_harness.rb', line 338

def check_provider(provider_name, timeout: nil, executor: nil, provider_runtime: nil)
  options = {}
  options[:timeout] = timeout unless timeout.nil?
  options[:executor] = executor unless executor.nil?
  options[:provider_runtime] = provider_runtime unless provider_runtime.nil?
  ProviderHealthCheck.check(provider_name, **options)
end

.check_providers(timeout: nil, executor: nil, provider_runtime: nil) ⇒ Array<Hash>

Check health of all configured providers.

Validates each enabled provider through registration, CLI availability, authentication, provider health status, and config validation checks.

Parameters:

  • timeout (Integer) (defaults to: nil) —

    timeout in seconds for each check (defaults to configured value)

Returns:

  • (Array<Hash>) —

    health status for each provider

Raises:

  • (ArgumentError) —

    if provider_runtime is supplied; runtime overrides are only supported by ‘check_provider` to avoid leaking one provider’s execution context into every other health check



325
326
327
328
329
330
331
332
 
# File 'lib/agent_harness.rb', line 325

def check_providers(timeout: nil, executor: nil, provider_runtime: nil)
  raise ArgumentError, "provider_runtime is only supported for single-provider health checks" unless provider_runtime.nil?

  options = {}
  options[:timeout] = timeout unless timeout.nil?
  options[:executor] = executor unless executor.nil?
  ProviderHealthCheck.check_all(**options)
end

.conductor ⇒ Orchestration::Conductor

Returns the global conductor for orchestrated requests

Returns:



68
69
70
 
# File 'lib/agent_harness.rb', line 68

def conductor
  @conductor ||= Orchestration::Conductor.new(config: configuration)
end

.configuration ⇒ Configuration

Returns the global configuration instance

Returns:



33
34
35
 
# File 'lib/agent_harness.rb', line 33

def configuration
  @configuration ||= Configuration.new
end

.configure {|Configuration| ... } ⇒ void

This method returns an undefined value.

Configure AgentHarness with a block

Yields:



40
41
42
 
# File 'lib/agent_harness.rb', line 40

def configure
  yield(configuration) if block_given?
end

.dependency_updater ⇒ DependencyUpdater

Returns the global dependency updater for managing agent tool versions.

The dependency updater applies a configurable cooldown period before adopting new upstream releases, reducing exposure to regressions.

Returns:



352
353
354
 
# File 'lib/agent_harness.rb', line 352

def dependency_updater
  @dependency_updater ||= DependencyUpdater.new
end

.discover_extensions(directory) ⇒ Array<Extensions::Base>

Discover and register all extensions found in a directory.

Parameters:

  • directory (String) —

    directory to scan

Returns:



103
104
105
 
# File 'lib/agent_harness.rb', line 103

def discover_extensions(directory)
  configuration.discover_extensions(directory)
end

.extension(reference) ⇒ Extensions::Base

Resolve a canonical extension definition by name or inline object.

Parameters:

Returns:



86
87
88
 
# File 'lib/agent_harness.rb', line 86

def extension(reference)
  configuration.resolve_extension(reference)
end

.extension_compatibility(provider:, extensions:) ⇒ Array<Extensions::CompatibilityReport>

Build a compatibility report for extensions against a provider.

Parameters:

Returns:



112
113
114
115
116
117
118
119
120
121
 
# File 'lib/agent_harness.rb', line 112

def extension_compatibility(provider:, extensions:)
  provider_instance = provider.is_a?(Providers::Base) ? provider : self.provider(provider)

  Array(extensions).map do |extension_ref|
    Extensions::Compatibility.report(
      provider: provider_instance,
      extension: extension(extension_ref)
    )
  end
end

.install_contract(name) ⇒ Hash

Get install contract metadata for a provider

Parameters:

  • name (Symbol, String) —

    the provider name

Returns:

  • (Hash) —

    install contract metadata

Raises:



178
179
180
 
# File 'lib/agent_harness.rb', line 178

def install_contract(name)
  Providers::Registry.instance.install_contract(name)
end

.installation_contract(provider_name, **options) ⇒ Hash?

Get installation metadata for a provider CLI.

Parameters:

  • provider_name (Symbol, String) —

    the provider name

  • options (Hash) —

    optional target selection (for example, ‘version:`)

Returns:

  • (Hash, nil) —

    installation contract

Raises:



206
207
208
 
# File 'lib/agent_harness.rb', line 206

def installation_contract(provider_name, **options)
  Providers::Registry.instance.installation_contract(provider_name, **options)
end

.installation_contracts ⇒ Hash<Symbol, Hash>

Get all provider installation contracts exposed by agent-harness.

Returns:

  • (Hash<Symbol, Hash>) —

    installation contracts keyed by provider



212
213
214
 
# File 'lib/agent_harness.rb', line 212

def installation_contracts
  Providers::Registry.instance.installation_contracts
end

.load_extensions(path, adapter: nil) ⇒ Array<Extensions::Base>

Load one or more extensions from disk through an adapter.

Parameters:

  • path (String) —

    extension file, directory, or package root

  • adapter (Symbol, String, nil) (defaults to: nil) —

    optional explicit adapter

Returns:



95
96
97
 
# File 'lib/agent_harness.rb', line 95

def load_extensions(path, adapter: nil)
  configuration.load_extensions(path, adapter: adapter)
end

.logger ⇒ Logger?

Returns the global logger

Returns:

  • (Logger, nil) —

    the configured logger



56
57
58
 
# File 'lib/agent_harness.rb', line 56

def logger
  configuration.logger
end

.provider(name) ⇒ Providers::Base

Get a provider instance

Parameters:

  • name (Symbol) —

    the provider name

Returns:



143
144
145
 
# File 'lib/agent_harness.rb', line 143

def provider(name)
  conductor.provider_manager.get_provider(name)
end

.provider_class(name) ⇒ Class

Look up the provider class for a given name or alias

Parameters:

  • name (Symbol, String) —

    the provider name or alias

Returns:

  • (Class) —

    the provider class

Raises:



159
160
161
 
# File 'lib/agent_harness.rb', line 159

def provider_class(name)
  Providers::Registry.instance.get(name)
end

.provider_install_contract(provider_name, version: nil) ⇒ Hash?

Returns install metadata for a provider CLI when the provider exposes it.

Parameters:

  • provider_name (Symbol, String) —

    the provider name

  • version (String, nil) (defaults to: nil) —

    optional explicit CLI version override

Returns:

  • (Hash, nil) —

    installation metadata



187
188
189
 
# File 'lib/agent_harness.rb', line 187

def provider_install_contract(provider_name, version: nil)
  provider_installation_contract(provider_name, **(version ? {version: version} : {}))
end

.provider_installation_contract(name, **options) ⇒ Hash?

Get the installation contract for a provider CLI.

Parameters:

  • name (Symbol, String) —

    the provider name

  • options (Hash) —

    optional target selection (for example, ‘version:`)

Returns:

  • (Hash, nil) —

    provider installation contract for the requested target

Raises:



197
198
199
 
# File 'lib/agent_harness.rb', line 197

def provider_installation_contract(name, **options)
  Providers::Registry.instance.installation_contract(name, **options)
end

.provider_metadata(provider_name, refresh: false) ⇒ Hash

Get consolidated metadata for a provider.

Parameters:

  • provider_name (Symbol, String) —

    the provider name or alias

  • refresh (Boolean) (defaults to: false) —

    when true, refresh live runtime metadata such as CLI availability instead of reusing cached values

Returns:

  • (Hash) —

    provider metadata

Raises:



223
224
225
 
# File 'lib/agent_harness.rb', line 223

def provider_metadata(provider_name, refresh: false)
  Providers::Registry.instance.provider_metadata(provider_name, refresh: refresh)
end

.provider_metadata_catalog(refresh: false) ⇒ Hash<Symbol, Hash>

Get consolidated metadata for all registered providers.

Parameters:

  • refresh (Boolean) (defaults to: false) —

    when true, refresh live runtime metadata such as CLI availability instead of reusing cached values

Returns:

  • (Hash<Symbol, Hash>) —

    provider metadata keyed by canonical provider



232
233
234
 
# File 'lib/agent_harness.rb', line 232

def provider_metadata_catalog(refresh: false)
  Providers::Registry.instance.provider_metadata_catalog(refresh: refresh)
end

.provider_smoke_test_contract(provider_name) ⇒ Hash?

Get smoke-test metadata for a provider CLI when the provider exposes it.

Parameters:

  • provider_name (Symbol, String) —

    the provider name

Returns:

  • (Hash, nil) —

    smoke-test contract



240
241
242
 
# File 'lib/agent_harness.rb', line 240

def provider_smoke_test_contract(provider_name)
  smoke_test_contract(provider_name)
end

.providers ⇒ Array<Symbol>

List all registered provider names

Returns:

  • (Array<Symbol>) —

    canonical provider names



150
151
152
 
# File 'lib/agent_harness.rb', line 150

def providers
  Providers::Registry.instance.all
end

.refresh_auth(provider_name, token: nil) ⇒ Hash

Refresh authentication credentials for a provider

Parameters:

  • provider_name (Symbol) —

    the provider name

  • token (String, nil) (defaults to: nil) —

    OAuth token to store

Returns:

  • (Hash) —

    result with :success key

Raises:



311
312
313
 
# File 'lib/agent_harness.rb', line 311

def refresh_auth(provider_name, token: nil)
  Authentication.refresh_auth(provider_name, token: token)
end

.refresh_auth_supported?(provider_name) ⇒ Boolean

Check whether credential refresh is supported for a provider

Parameters:

  • provider_name (Symbol) —

    the provider name

Returns:

  • (Boolean) —

    true if refresh_auth can be called for the provider

Raises:



302
303
304
 
# File 'lib/agent_harness.rb', line 302

def refresh_auth_supported?(provider_name)
  Authentication.refresh_auth_supported?(provider_name)
end

.reset! ⇒ void

This method returns an undefined value.

Reset configuration to defaults (useful for testing)



46
47
48
49
50
51
52
 
# File 'lib/agent_harness.rb', line 46

def reset!
  @configuration = nil
  @conductor = nil
  @token_tracker = nil
  @dependency_updater = nil
  Skills.reset! if defined?(Skills)
end

.resolve_latest_version(provider_name, bypass_cooldown: false) ⇒ Hash?

Resolve the latest eligible version for an installable provider tool, applying the configured cooldown period.

Parameters:

  • provider_name (Symbol, String) —

    the provider name

  • bypass_cooldown (Boolean) (defaults to: false) —

    when true, skip the cooldown check

Returns:

  • (Hash, nil) —

    version info with :provider, :version, :released_at, :installation_contract keys, or nil when no eligible version exists



363
364
365
366
367
368
 
# File 'lib/agent_harness.rb', line 363

def resolve_latest_version(provider_name, bypass_cooldown: false)
  dependency_updater.resolve_latest_installation_contract(
    provider_name,
    bypass_cooldown: bypass_cooldown
  )
end

.send_message(prompt, provider: nil, executor: nil, **options) ⇒ Response

Send a message using the orchestration layer

Parameters:

  • prompt (String) —

    the prompt to send

  • provider (Symbol, nil) (defaults to: nil) —

    optional provider override

  • executor (CommandExecutor, nil) (defaults to: nil) —

    per-request executor override

  • options (Hash) —

    additional options

Returns:

  • (Response) —

    the response from the provider



78
79
80
 
# File 'lib/agent_harness.rb', line 78

def send_message(prompt, provider: nil, executor: nil, **options)
  conductor.send_message(prompt, provider: provider, executor: executor, **options)
end

.smoke_test_contract(provider_name) ⇒ Hash?

Get smoke-test metadata for a provider CLI.

Parameters:

  • provider_name (Symbol, String) —

    the provider name

Returns:

  • (Hash, nil) —

    smoke-test contract

Raises:



248
249
250
251
252
 
# File 'lib/agent_harness.rb', line 248

def smoke_test_contract(provider_name)
  # Explicitly raise if provider is not registered to match documentation
  raise ConfigurationError, "Unknown provider: #{provider_name}" unless Providers::Registry.instance.registered?(provider_name)
  Providers::Registry.instance.smoke_test_contract(provider_name)
end

.smoke_test_contracts ⇒ Hash<Symbol, Hash>

Get all provider smoke-test contracts exposed by agent-harness.

Returns:

  • (Hash<Symbol, Hash>) —

    smoke-test contracts keyed by provider



256
257
258
 
# File 'lib/agent_harness.rb', line 256

def smoke_test_contracts
  Providers::Registry.instance.smoke_test_contracts
end

.sub_agent(reference) ⇒ SubAgentConfig

Resolve a canonical sub-agent definition by name or inline payload.

Parameters:

Returns:



127
128
129
 
# File 'lib/agent_harness.rb', line 127

def sub_agent(reference)
  configuration.resolve_sub_agent(reference)
end

.token_tracker ⇒ TokenTracker

Returns the global token tracker

Returns:



62
63
64
 
# File 'lib/agent_harness.rb', line 62

def token_tracker
  @token_tracker ||= TokenTracker.new
end

.translate_sub_agent(reference, provider:) ⇒ Hash

Translate a canonical sub-agent definition into a provider-specific format.

Parameters:

  • reference (Symbol, String, Hash, SubAgentConfig) —

    sub-agent reference

  • provider (Symbol, String) —

    target provider

Returns:

  • (Hash) —

    provider-specific sub-agent definition



136
137
138
 
# File 'lib/agent_harness.rb', line 136

def translate_sub_agent(reference, provider:)
  SubAgentTranslator.for_provider(provider, sub_agent(reference))
end