{"type":"post","id":"step-by-step-guide-build-a-voice-agent-259b68","slug":"step-by-step-guide-build-a-voice-agent-259b68","title":"Step by Step guide: Build a Voice Agent That Never Goes Silent using ADK","description":"Google’s guide presents a concrete runtime problem: a voice agent that waits synchronously for a slow tool can leave the caller in silence.","retrieval_nugget":"Google’s guide presents a concrete runtime problem: a voice agent that waits synchronously for a slow tool can leave the caller in silence.","published_at":"2026-10-19","updated_at":"2026-10-19","record_date":"2026-10-19","date_kind":"published_at","topics":["google"],"source_urls":["https://developers.googleblog.com/step-by-step-guide-build-a-voice-agent-that-never-goes-silent-using-adk"],"schema_version":"newruntime-agent-readable-v0.2","stable_id":"post:step-by-step-guide-build-a-voice-agent-259b68","status":"published","visuals":[],"editorial_provenance":{"schema_version":"newruntime-editorial-copy-v1","content_status":"source_grounded_final","final_copy_sha256":"sha256:20cb2d7ba50cd9ab26ac9f452c96863cb958afe770b08382d1f79aae006bc9e4","reviewed_at":"2026-10-19T20:07:41.592Z","source_evidence_count":1,"verified_claim_count":2,"site_analysis_schema_version":"newruntime-site-analysis-v1","site_object_kind":"field_note","observed_fact_count":2,"implication_count":1,"watch_condition_count":1,"related_record_count":0},"analysis":{"schema_version":"newruntime-site-analysis-v1","object_kind":"field_note","thesis":"responsive voice agents need tool execution that can continue without blocking the conversational loop.","observed_facts":[{"text":"Google’s guide describes ADK streaming tools that yield progress updates while work continues.","source_urls":["https://developers.googleblog.com/step-by-step-guide-build-a-voice-agent-that-never-goes-silent-using-adk"]},{"text":"In Google’s sales-report workflow on Gemini 3.8 Live, switching from a blocking to a streaming tool reduced time to first words from 14.4 seconds to 1.2 seconds.","source_urls":["https://developers.googleblog.com/step-by-step-guide-build-a-voice-agent-that-never-goes-silent-using-adk"]}],"mechanism":"ADK streaming tools yield progress updates while work continues, whereas background execution suits tasks where repeated narration would be intrusive. Response scheduling then controls how the eventual result re-enters the conversation.","why_now":"live voice exposes backend latency as conversational dead air, making execution design directly perceptible to users.","implications":["Teams building voice agents can test asynchronous tool patterns against their own slow queries instead of relying on prompts to mask waits."],"evidence_boundary":"the latency comparison is a Google-reported benchmark for one workflow, not an independent or general performance result.","watch_conditions":["whether ADK implementations handle duplicate tool calls, cancellation, and delivery timing reliably under real workloads."],"related_records":[],"new_branch_reason":"No prior New Runtime record is supplied; this guide supports a distinct record on non-blocking voice-agent tool execution."},"editor":{"role":"editor","name":"Andrey Reshetnikov","profile":"https://newruntime.com/owner-profile.md","profile_json":"https://newruntime.com/owner-profile.json","same_as":["https://www.linkedin.com/in/reshetnikov1/","https://t.me/lapetuse"]},"routes":{"html":"https://newruntime.com/posts/step-by-step-guide-build-a-voice-agent-259b68/","markdown":"https://newruntime.com/posts/step-by-step-guide-build-a-voice-agent-259b68.md","json":"https://newruntime.com/posts/step-by-step-guide-build-a-voice-agent-259b68.json"},"related_patterns":["runtime-observability-becomes-the-primary-engineering-focus-for-ai"],"next_reads":[{"type":"topic","path":"/topics/google/","url":"https://newruntime.com/topics/google/","title":"Google","reason":"Explore the google topic hub.","media_type":"text/html","markdown_url":"https://newruntime.com/topics/google.md","json_url":"https://newruntime.com/topics/google.json"},{"type":"collection","path":"/posts/","url":"https://newruntime.com/posts/","title":"Field Notes","reason":"Open the latest editorial analysis.","media_type":"text/html","json_url":"https://newruntime.com/posts.json"},{"type":"collection","path":"/source-ledger.json","url":"https://newruntime.com/source-ledger.json","title":"Source Ledger","reason":"Inspect the public source evidence graph.","media_type":"application/json"}]}