;
};
**Level 2 – Lesson 6 of 8** – Configure speech recognition to reduce misrecognition and improve routing.
[ASR](/voice-channel/advanced/call-settings#keyphrases) determines what the agent *hears*. Every downstream system depends on it: retrieval, routing, response control, handoff logic. Small transcription errors here silently break otherwise well-designed agents. Global ASR is where you correct systematic listening problems at the source.
## What global ASR is for
Minimize unnecessary clarification questions
Increase routing accuracy for calls
Improve Knowledge topic selection for spoken queries
Correct recurring transcription errors at the source
Global ASR is not a substitute for good KB design or clear agent behavior rules. It improves transcription accuracy – it does not add new knowledge to the agent.
## Which tool to use
```mermaid theme={"theme":{"light":"github-light","dark":"github-dark"}}
flowchart TD
A[ASR problem identified] --> B{What type of error?}
B -->|Word is correct but under-recognized| C[Keyphrase Boosting]
B -->|ASR consistently hears the wrong thing| D[Transcript Corrections]
C --> E[Add keyphrase → start with Default bias strength]
D --> F[Add correction → define misheard expression and replacement]
E --> G[Test in Call → increase bias only if errors persist]
F --> G
G --> H{Improvement confirmed?}
H -->|Yes| I[Promote carefully]
H -->|No| B
```
## Two essential tools
Keyphrase Boosting biases the ASR model toward recognizing specific words or phrases more reliably.
### When to use it
* A word is important for routing or actions
* Misrecognition causes the agent to take the wrong path
* Users consistently repeat themselves for the same term
**Department names:**
* "front desk"
* "billing"
* "room reservations"
**Product or service names:**
* "bell desk"
* "late checkout"
**Action-critical verbs:**
* "cancel"
* "confirm"
### How to configure
Enter it exactly as you want it recognized
Start with Default bias strength
Increase toward Maximum only if errors persist
**Important guidance:**
* Bias strength is cumulative. Over-biasing many terms can degrade overall accuracy
* Avoid boosting generic words like "room" unless they are routing-critical
* Prefer multi-word phrases over single words when possible
* **Example:** If callers asking for the "bell desk" are frequently routed incorrectly, boost "bell desk" rather than boosting "desk"
Transcript Corrections rewrite text after transcription, mapping common errors to the intended phrase.
### When to use it
* ASR consistently hears the same wrong thing
* Accents or homophones cause predictable errors
* Brand or proper names are repeatedly mangled
**Homophones:**
* "copper" → "hopper"
**Accent-driven substitutions:**
* "reef fund" → "refund"
**Brand names:**
* "Hopper Consumer" → "Hopper"
### How to configure
Select substring or regex
Enter what ASR incorrectly transcribes
Enter the intended replacement text
**Important guidance:**
* Prefer narrow matches over broad regex
* Avoid corrections that could unintentionally rewrite unrelated phrases
* If unsure, test in Sandbox with real call audio before promoting
* **Example:** If "cancel" is sometimes transcribed as "council," add a correction rather than increasing bias on "cancel" alone
## Check your understanding
## A practical workflow
Look for calls where:
* The agent asked for repetition
* The wrong KB topic was selected
* Routing or handoff failed unexpectedly
Find the specific word or phrase that failed
Decide:
* **Boost** if the word is correct but under-recognized
* **Correct** if the word is consistently misheard as something else
Make the smallest possible adjustment
Verify the improvement
Only promote after confirming improvement
## Common mistakes
**Avoid these pitfalls:**
* Boosting everything "just in case"
* Using Transcript Corrections to fix KB design problems
* Applying maximum bias globally without testing
* Forgetting that local (flow-level) ASR settings override global ones
## Check your understanding
## Verification checklist
Verification is complete when:
* Previously misheard phrases are transcribed correctly
* The agent asks fewer clarification questions for known terms
* Routing and KB selection stabilise in live call testing
* Behavior remains consistent after promotion between environments
Global ASR tuning is iterative. Small, deliberate adjustments here pay off more than large rewrites elsewhere.
## Try it yourself
A caller says "I'd like a refund" but ASR consistently transcribes it as "I'd like a reef fund". The `refund_request` topic therefore never triggers.
Answer:
1. Should you use Keyphrase Boosting or Transcript Corrections – and why?
2. Write the full configuration.
Ask yourself: is ASR hearing the right word but recognizing it poorly, or is it consistently mishearing one thing as another?
1. **Transcript Corrections** – because ASR is consistently mishearing "refund" as "reef fund". This is a predictable substitution error, not an under-recognition problem.
2. **Configuration:**
* **Match type:** Substring
* **Misheard expression:** `reef fund`
* **Correction:** `refund`
## Check your understanding
Lesson 5 of 8
Lesson 7 of 8