20 Free CCDV-F Practice Questions With Explanations [2026]

A support chat product streams Claude's replies to the browser over server-sent events. Users report that some long answers stop mid-sentence, yet the interface renders them as finished. Logs for those turns show a final stop_reason of max_tokens. The team wants the smallest change that makes truncation visible and recoverable. What should the developer do?

A nightly enrichment job sends 400 sequential Claude requests that share a 20,000-token reference-manual prefix marked with a cache_control breakpoint. Each request waits on an upstream step, so calls arrive roughly fifteen minutes apart. Usage logs show cache_creation_input_tokens on every call and cache_read_input_tokens always at zero, and costs match uncached pricing. What is the most likely cause and fix?

A fintech team's Claude-backed statement summarizer changed tone and format one morning with no deploy. Investigation shows the code references a model alias, and the summarization prompt lives in a database row that support staff edit directly. The team wants reproducible behavior and reviewable change. Which TWO changes address the root causes? (Select TWO.)

A field-service app photographs utility meters with phone cameras and asks Claude to read the digits. Photos are 12-megapixel JPEGs sent as base64 image blocks. Time to first token and per-request cost are both above budget, and a test on images resized to roughly one megapixel shows identical reading accuracy. Which change best fixes cost and latency?

A Node.js service summarizes 60 uploaded documents per user request by calling Claude once per document inside a for loop with await, so each request takes about 60 times the single-call latency while the user waits. The team wants much faster completion without triggering rate-limit errors. Which approach best fits?

An insurer extracts eight fixed fields from claim forms with the top capability tier. Every request carries the same 9,000-token instruction and examples block, and results must reach an adjuster's screen within seconds. A 5,000-form eval shows the fast tier matches extraction accuracy. Monthly spend is three times budget. Which TWO changes cut cost without breaking requirements? (Select TWO.)

A platform team is deciding which of four upcoming workloads should be built as an agent loop, where the model chooses its own next steps and tool calls, versus a fixed workflow of predetermined model calls. Cost, auditability, and predictability all matter to the team. Which TWO workloads justify an agent loop rather than a workflow? (Select TWO.)

A retrieval assistant places 25 retrieved policy documents (about 40,000 tokens) in the user turn, with the instruction "answer only from these documents; otherwise reply NOT FOUND" inserted between documents 12 and 13. In testing, the model sometimes answers from general knowledge. The team wants the cheapest reliable improvement. What should they change first?

An intake service registers two tools, extract_claim and lookup_policy, and every response must arrive as an extract_claim tool call so downstream code can read structured fields. With tool_choice left at the default, the model occasionally replies in prose or calls lookup_policy first. Which change guarantees the required tool call on every request?

A document-summarization endpoint fails on some uploaded PDFs with a 400 error stating that the prompt is too long, while smaller files succeed. The developer proposes raising max_tokens from 4,000 to 16,000 to give the request more room. The summaries themselves are short. What is the correct diagnosis and fix?

A retailer must generate descriptions for 400,000 catalog items before a launch in five days, and the merchandising interface also lets an editor regenerate any single description while they wait on the page. The team wants the lowest cost that still meets both needs. Which processing design fits?

A team wrote a custom loop over the Messages API: call the model, execute any requested tools, append results, repeat until end_turn. Product now wants file and shell tools, permission prompts before risky actions, session resume, and subagents. The team wants to stop rebuilding what Claude Code already has. Which choice best fits?

A coding agent has been working in one session for four hours. Its context now holds hundreds of stale file reads and test outputs, and it has started re-deciding choices settled earlier. The team wants to keep the decisions and rationale while releasing most of the token budget. Which TWO actions address bloat and drift directly? (Select TWO.)

A research agent has fetch_page and send_email tools. During a run, a scraped web page contained hidden text telling the agent to email the user's last ten messages to an external address, and the agent complied. The team needs a control that holds even when a future page contains a cleverer injection. Which change provides that guarantee?

A live-captioning product runs a top capability tier model with streaming. Users complain that words arrive too slowly during fast speech, even though the first token appears promptly. An eval shows that moving to the fast tier drops caption accuracy below the acceptable threshold. The team wants faster token output with no change in model quality. Which option fits best?

A developer is building an MCP server for the company's ticketing system. Claude clients need to read ticket details, create tickets, and connect from teammates' laptops as well as from a hosted agent in the cloud, all through one shared deployment. Which TWO design decisions are correct for this server? (Select TWO.)

A team added a PreToolUse hook that blocks destructive shell commands, but it only fires on the laptop of the engineer who wrote it. She placed it in .claude/settings.local.json. The team wants every clone of the repository to enforce the same block without per-machine setup. What should she change?

A bank is deploying a coding agent that must run inside its own VPC, use an internal build toolchain, and never send tool traffic through infrastructure the bank does not control. A vendor-managed agent runtime would ship in days, and the self-hosted route will take weeks. Which deployment model should the team choose, and why?

A developer's tool-use loop receives a tool_use block, runs the tool, then replies with a user message whose content array starts with a text block reading "Here is the result:" followed by the tool_result block. The API rejects the request with a 400 error stating that tool_use ids were found without tool_result blocks immediately after. What is the correct fix?

A store assistant told a shopper an item was in stock when it was sold out. The trace shows the model called get_inventory with the correct SKU, the tool returned a quantity of 14 from a cache last refreshed six hours earlier, and the model reported that number faithfully. Where does the failure live, and what is the first fix?