Class: Phronomy::Tool::Base

Inherits:
RubyLLM::Tool
  • Object
show all
Defined in:
lib/phronomy/tool/base.rb

Overview

Base class extending RubyLLM::Tool with Phronomy-specific DSL.

Additional DSL over RubyLLM::Tool:

  • tool_name : explicit function name exposed to the LLM (overrides auto-conversion)
  • scope : access-scope metadata (:read_only, :write, etc.)
  • on_error : error-handling policy (:raise or :return_empty)
  • on_schema_error : behavior when LLM passes schema-violating arguments :return_error (default), :raise, or :coerce
  • requires_approval : require human approval before execution
  • param :name, enum: [...] : restrict allowed values in the JSON Schema

Examples:

class SearchKnowledgeBase < Phronomy::Tool::Base
  tool_name "search_kb"               # explicit name shown to the LLM
  description "Search the internal knowledge base"
  param :query,  type: :string, desc: "Search query"
  param :lang,   type: :string, desc: "Language", required: false, enum: %w[en ja fr]
  scope :read_only
  on_error :return_empty

  def execute(query:, lang: "en")
    KnowledgeBase.search(query, lang: lang)
  end
end

Direct Known Subclasses

AgentTool, McpTool

Class Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Class Attribute Details

._sleep_proc ⇒ #call

Injectable sleep callable for testing. Defaults to Kernel#sleep.

Returns:



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# File 'lib/phronomy/tool/base.rb', line 130

def _sleep_proc
  @_sleep_proc || method(:sleep)
end

Class Method Details

.on_error(behavior = nil) ⇒ Object

Configures error-handling behavior.

Parameters:

  • behavior (Symbol) (defaults to: nil) —

    :raise (default) or :return_empty



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# File 'lib/phronomy/tool/base.rb', line 71

def on_error(behavior = nil)
  return @on_error || :raise if behavior.nil?

  @on_error = behavior
end

.on_schema_error(behavior = nil) ⇒ Object

Configures how this tool responds when the LLM passes arguments that violate the declared parameter types or enum constraints.

Parameters:

  • behavior (Symbol) (defaults to: nil) —

    :return_error (default) — return a descriptive error string as the tool result so the LLM can self-correct on the next turn. :raise — raise Phronomy::ToolError, stopping the agent loop. :coerce — attempt type coercion (e.g. "42" → 42 for :integer); falls back to :return_error when coercion is not possible.



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# File 'lib/phronomy/tool/base.rb', line 86

def on_schema_error(behavior = nil)
  return @on_schema_error || :return_error if behavior.nil?

  @on_schema_error = behavior
end

.param(name, enum: nil, **options) ⇒ Object

Extends RubyLLM::Tool.param with an optional +enum:+ keyword. The enum values are stored separately and injected into the JSON Schema produced by #params_schema.

Parameters:

  • name (Symbol) —

    parameter name

  • enum (Array, nil) (defaults to: nil) —

    allowed values; when given, added as "enum" in JSON Schema

  • options (Hash) —

    forwarded to RubyLLM::Tool.param



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# File 'lib/phronomy/tool/base.rb', line 49

def param(name, enum: nil, **options)
  super(name, **options)
  param_enums[name] = enum if enum
end

.param_enums ⇒ Hash{Symbol => Array}

Returns the enum constraints registered via .param.

Returns:

  • (Hash{Symbol => Array}) 


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# File 'lib/phronomy/tool/base.rb', line 56

def param_enums
  @param_enums ||= {}
end

.requires_approval(value = nil) ⇒ Object

Configures whether human approval is required before executing this tool.

Parameters:

  • value (Boolean) (defaults to: nil) 


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# File 'lib/phronomy/tool/base.rb', line 94

def requires_approval(value = nil)
  return @requires_approval || false if value.nil?

  @requires_approval = value
end

.retry_on(*exception_classes, times: 1, wait: 0, base: 1.0) ⇒ Object

Registers a retry policy for one or more exception classes.

When the tool raises one of the listed exception classes, it will be retried up to +times+ times with the specified wait strategy. Multiple policies can be registered and are evaluated in order.

GuardrailError is never retried regardless of this configuration.

Examples:

retry_on Phronomy::ToolError, times: 3, wait: :exponential, base: 1.0
retry_on Net::ReadTimeout, times: 2, wait: 0.5

Parameters:

  • exception_classes (Array<Class>) —

    exception classes to retry on

  • times (Integer) (defaults to: 1) —

    maximum retry attempts (default: 1)

  • wait (Symbol, Numeric) (defaults to: 0) —

    :exponential, :linear, or a fixed Float

  • base (Float) (defaults to: 1.0) —

    base wait time in seconds (default: 1.0)



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# File 'lib/phronomy/tool/base.rb', line 116

def retry_on(*exception_classes, times: 1, wait: 0, base: 1.0)
  @retry_policies ||= []
  @retry_policies << {exceptions: exception_classes, times: times, wait: wait, base: base}
end

.retry_policies ⇒ Array<Hash>

Returns all retry policies registered on this tool class.

Returns:

  • (Array<Hash>) 


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# File 'lib/phronomy/tool/base.rb', line 123

def retry_policies
  @retry_policies || []
end

.scope(value = nil) ⇒ Object

Sets the access scope for this tool (metadata; enforcement is the responsibility of the Graph/Guardrail layer).

Parameters:

  • value (Symbol) (defaults to: nil) —

    e.g. :read_only, :write, :admin



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# File 'lib/phronomy/tool/base.rb', line 63

def scope(value = nil)
  return @scope if value.nil?

  @scope = value
end

.tool_name(value = nil) ⇒ Object

Sets an explicit function name to expose to the LLM, bypassing RubyLLM's automatic CamelCase-to-snake_case conversion. When omitted, RubyLLM's default conversion applies (e.g. WeatherTool → "weather").

Parameters:

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

    the exact function name the LLM will see



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# File 'lib/phronomy/tool/base.rb', line 36

def tool_name(value = nil)
  return @tool_name if value.nil?

  @tool_name = value.to_s
end

Instance Method Details

#call(args) ⇒ Object

Overrides RubyLLM::Tool#call to apply schema validation, the retry policy, the on_error policy, and wrap errors as ToolError.

Execution order:

  1. Schema validation (type + enum checks).
  2. Call super(validated_args) inside a retry loop.
  3. On persistent failure, apply on_error policy.


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# File 'lib/phronomy/tool/base.rb', line 173

def call(args)
  validated_args, schema_error = validate_and_coerce(args)
  if schema_error
    case self.class.on_schema_error
    when :raise
      raise Phronomy::ToolError, "#{self.class.name} schema error: #{schema_error}"
    else
      # :return_error (default) and coerce fallback
      return "Schema validation failed: #{schema_error}"
    end
  end
  with_tool_retry { super(validated_args) }
rescue Phronomy::ToolError
  raise
rescue => e
  case self.class.on_error
  when :return_empty
    []
  else
    raise Phronomy::ToolError, "#{self.class.name} execution failed: #{e.message}"
  end
end

#execute(**_args) ⇒ String

This method is abstract.

Subclasses must implement this method.

Override this method to implement the tool's logic.

The method receives the declared param fields as keyword arguments. The return value is passed back to the LLM as the tool result.

Examples:

class WeatherTool < Phronomy::Tool::Base
  description "Get current weather"
  param :location, type: :string, desc: "City name"

  def execute(location:)
    WeatherService.fetch(location).to_s
  end
end

Returns:

  • (String) —

    result string returned to the LLM

Raises:

  • (NotImplementedError) 


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# File 'lib/phronomy/tool/base.rb', line 217

def execute(**_args)
  raise NotImplementedError, "#{self.class}#execute is not implemented"
end

#name ⇒ Object

Returns the function name exposed to the LLM. Uses the class-level tool_name if set; otherwise falls back to RubyLLM's automatic conversion (CamelCase → snake_case, strips trailing "_tool").



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# File 'lib/phronomy/tool/base.rb', line 142

def name
  self.class.tool_name || super
end

#params_schema ⇒ Object

Returns the JSON Schema for this tool's parameters. Injects "enum" entries for any param declared with enum: [...].



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# File 'lib/phronomy/tool/base.rb', line 148

def params_schema
  schema = super
  return schema if schema.nil? || self.class.param_enums.empty?

  enums = self.class.param_enums
  properties = schema.dig("properties") || schema.dig(:properties)
  return schema unless properties

  enums.each do |param_name, values|
    key = properties.key?(param_name.to_s) ? param_name.to_s : param_name.to_sym
    next unless properties[key]

    properties[key]["enum"] = values.map(&:to_s)
  end

  schema
end

#requires_approval? ⇒ Boolean

Instance method for requires_approval? (convenience accessor).

Returns:

  • (Boolean) 


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# File 'lib/phronomy/tool/base.rb', line 197

def requires_approval?
  self.class.requires_approval
end