1.3 Hybrid Reasoning: Agent Script in Canvas View and Script View

1.3 Hybrid Reasoning: Agent Script in Canvas View and Script View

Quick Answer: Hybrid reasoning is Salesforce's term for combining programmatic expressions (conditions, variables, transitions, deterministic actions) with natural-language instructions in the same Agent Script block. Logic handles workflow and business rules predictably, and the LLM handles conversation. Agentforce Builder exposes the same script in Canvas view (a visual, block-based editor) and Script view (direct code editing).

Why Hybrid Reasoning Exists

Prompt-only agents create a familiar enterprise problem. You can instruct an LLM to verify a customer before sharing order details, but you can't guarantee it will follow that sequence every time. Adding more instructions often makes things worse. Salesforce's context-engineering guidance names three failure patterns:

Components of hybrid reasoning

• Logic instructions (->): if/else conditions, run actions, set variables, and transition to another subagent. They execute in order, exactly as written, before reasoning.
• Prompt instructions (|): natural-language guidance, personalized with template expressions such as {!@variables.member_name}.
• Reasoning actions: tools and utilities the LLM may choose, including transitions, escalation, and setting variables. Each can carry a filter (available when).
• Variables: reliable state storage, so the agent doesn't depend on the LLM remembering a value.
• after_reasoning: deterministic logic that runs after the reasoning loop, such as a mandatory transition.
• Model override: a subagent can use a different model than the agent default. Model override is available only for agents created in the new builder.

Benefits the exam expects you to explain

1. Predictability for critical steps. Identity verification, eligibility checks, and required lookups run every time.
2. Smaller, more relevant prompts. Only the instructions that apply are resolved, which improves accuracy and reduces latency.
3. Reliable sequencing (action chaining). You can guarantee action A runs before action B and pass A's output into B through variables.
4. Flexible conversation. The LLM still handles phrasing, clarifying questions, and judgment where rules don't apply.
5. Easier troubleshooting. Deterministic paths are visible in the script and in the trace.

A Before-and-After Example

Prompt-only instruction (fragile):

| If the customer is a Gold member and their order is more than 30 days old,
| offer store credit. Otherwise explain the return policy.
| Always check the loyalty tier first.

The LLM has to remember to check the tier, interpret "more than 30 days," and choose a branch.

Hybrid version (reliable):

reasoning:
    instructions: ->
        if @variables.loyalty_tier == None:
            run @actions.get_loyalty_tier
                with contact_id = @variables.ContactId
                set @variables.loyalty_tier = @outputs.tier
        if @variables.loyalty_tier == "Gold":
            | Thank {!@variables.customer_name} for being a Gold member.
        if @variables.days_since_order > 30:
            | Explain that the order is outside the 30-day window and offer store credit.
        else:
            | Offer to start a return with @actions.create_return.

The lookup always happens and the date rule is applied by logic. The LLM receives only the one or two sentences that apply to this customer.

Canvas View

When you open an agent in Agentforce Builder, it opens in Canvas view. You see a view-only visual summary of the agent's details, router, and subagents. To edit, open a subagent or action page, or switch to Script view.

Script View

Script view is for advanced users who want to write Agent Script directly, with syntax highlighting, autocompletion, and validation. Key rules:

• Your configuration is consistent across both views; they're two representations of the same script.
• On save, the builder validates both views. Errors are underlined in Canvas, and Script view shows more detail.
• Some Script view changes can make Canvas view unavailable until you fix the errors in Script view.
• On macOS, Option+M switches between views.
• Developers can also work outside the browser: Agentforce DX retrieves the .agent file into a Salesforce DX project for VS Code, where the extension supports Agent Script editing and validation.

Versioning in the New Builder

A version must be committed before it can be activated. To change a committed or active agent, create a new draft, test it, commit it, and then activate it.

Legacy Builder vs. New Builder

Exam Traps

• "Hybrid" doesn't mean two separate agents. It means logic and prompts in the same instruction block.
• Canvas and Script views aren't separate configurations. An edit in one appears in the other.
• You can't activate a draft. Commit first.
• Put sensitive business rules in logic or in the action itself, not in prompt text alone. Salesforce's guidance is that instructions are nondeterministic and don't replace coded business rules.