CCAR-F Practice Test 3 — 30 Questions

Question 1

You are designing a code-migration assistant that converts legacy COBOL modules to a modern language. Stakeholders require high reliability and verifiable output. Which TWO architectural practices best support this requirement? (Choose two.)

Choose an answer to begin — your selection is scored in the full session.

Accepted Answer

Add an automated test harness that compiles and executes the generated code against representative legacy inputs and compares outputs.. Verifiable migration needs machine-checkable artifacts and empirical proof of behavior. A fixed schema plus structured report makes each response auditable, while a compile-and-execute harness compares generated behavior against known legacy outputs. Together they catch both structural and semantic defects. Creativity, monolithic responses, and silent omission of edge cases all reduce verifiability rather than strengthen it.

Answer

Request the entire migration in a single response to preserve the model's global understanding of the module.

Answer

Maximize the model's creativity by raising temperature so it can find novel modernization opportunities.

Answer

Allow the model to omit edge-case handling when the legacy code is ambiguous, to keep outputs concise.

Question 2

A document-triage agent uses Claude with a read_attachment tool. During testing, the agent calls read_attachment for a PDF, receives a tool_result containing the extracted text, and then immediately calls read_attachment again for the same file id, repeating several times until the orchestrator stops it. The tool itself works correctly and returns valid content each time. What is the most effective architectural fix?

Accepted Answer

Have the orchestrator detect repeated identical tool_use requests against the same arguments and short-circuit them by returning a cached tool_result or by injecting a message that the content was already provided.. Repeated identical tool calls with valid results indicate the agent is not recognizing that its need is already satisfied, so the robust fix is deterministic duplicate detection in the orchestrator, paired with cached results or an explicit signal that the content was already supplied. Timeouts, larger budgets, and inlining documents all leave the loop mechanism intact or trade away needed flexibility.

Answer

Raise the tool's timeout so the repeated calls have more time to complete and the agent stops retrying prematurely.

Answer

Remove read_attachment from the tools list and paste the document text directly into the system prompt for every request.

Answer

Increase the agent's iteration budget so it has more chances to break out of the repetition on its own.

Question 3

A regulated insurance workflow requires Claude to extract coverage limits from policy documents and return them as JSON. During testing, the model occasionally emits prose commentary before the JSON, breaking the downstream parser. The team cannot change the parser and must guarantee the response begins with a valid JSON object. Which technique most reliably enforces that?

Accepted Answer

Prefill the assistant turn with an opening brace so Claude continues from that point.. Prefilling the assistant turn with an opening brace constrains generation so the response starts inside a JSON object, satisfying a parser that cannot tolerate leading prose. Instructions and retries are probabilistic, temperature changes add variance, and shortening inputs does not affect output formatting. For a hard formatting guarantee, the prefill is the reliable control.

Answer

Shorten the policy documents before extraction so the model has less text to summarize.

Answer

Add the phrase 'respond only in JSON' to the end of the system prompt and retry on parse failure.

Answer

Raise the temperature to encourage the model to explore more structured output formats.

Question 4

An architect is onboarding a legacy service and wants Claude Code to build context quickly. The repository has 40,000 files, most of them generated build artifacts and vendored dependencies, and the team wants exploration to stay focused on first-party source. Which approach best keeps Claude Code's automatic context gathering efficient here?

Accepted Answer

Add ignore patterns for the generated and vendored directories in the project's ignore configuration so they are excluded from tool-driven discovery.. On very large repositories, the dominant cost is irrelevant files entering the model's discovery path. Ignore configuration is the supported, reversible lever: it filters generated and vendored content out of search and exploration while leaving first-party source fully reachable. Dumping a tree into the prompt, shrinking the working root, or deleting directories all either waste context, over-restrict scope, or cause collateral damage.

Answer

Delete the generated and vendored directories from the working copy before starting the session.

Answer

Paste the full directory tree into the first prompt so Claude has a complete map of the repository.

Answer

Run the session from inside the `src/` subdirectory so the working root is smaller.

Question 5

A developer frequently runs the same multi-step task in Claude Code: lint the changed files, run the unit tests, and then draft a commit message. They want to invoke this entire sequence with a single reusable command rather than retyping the instructions each time. Which Claude Code feature should they configure?

Accepted Answer

A custom slash command defined as a Markdown file in .claude/commands/. Custom slash commands are the documented Claude Code mechanism for packaging a reusable prompt as a Markdown file under .claude/commands/. Invoking the command sends the file's contents as the prompt, so a single command can drive linting, testing, and commit message drafting. Git aliases, shell scripts, and permission entries operate outside the model and cannot orchestrate that workflow.

Answer

An entry in the permissions.allow array of settings.json

Answer

A Git alias in .git/config

Answer

A shell script added to the PATH

Question 6

An architect is designing an MCP server that exposes a tool to retrieve employee records from an internal HR system. The tool accepts a 'department' parameter. To prevent the model from retrieving records outside the user's authorized departments, the architect wants to enforce access control at the MCP layer. Which approach best ensures that the model cannot bypass authorization?

Accepted Answer

Validate the requested department against the authenticated user's permissions on the MCP server before executing the HR system query, and return an authorization error if not permitted.. Authorization must be enforced at the MCP server using the authenticated user's identity, not delegated to the model or applied after data retrieval. By validating the requested department against the user's permissions before querying the HR system, the server creates a hard boundary that the model cannot circumvent. This aligns with least privilege and zero-trust principles.

Answer

Include a detailed description in the tool's JSON Schema stating that the model must only request departments the user is allowed to see.

Answer

Configure the MCP server to run with the same permissions as the HR system's service account, which has access to all departments, and rely on the model to request only allowed departments.

Answer

Add a post-processing step that filters the HR system's response to remove any records from departments the model was not supposed to request.

Question 7

An architect is designing a research agent whose context window is filling with raw web page HTML. The agent must keep working across dozens of sources without exceeding the context limit. Which architecture best preserves reasoning quality over a long session?

Accepted Answer

Run a sub-agent that reads each page and returns a structured summary, and keep only those summaries in the main agent's context.. Context management in agentic systems is an architectural concern, not a parameter tweak. Sub-agents act as context firewalls: they consume noisy inputs in their own window and return only distilled results to the orchestrator. This keeps the primary reasoning thread focused on high-signal tokens and enables the session to scale across many sources without truncation or attention dilution.

Answer

Store full page text in the conversation and rely on the model's long-context ability to attend to everything.

Answer

Increase the `max_tokens` output parameter so Claude can compress the HTML itself in one pass.

Answer

Set the model's temperature to zero so responses become shorter and consume fewer tokens.

Question 8

An architect is implementing an MCP server that exposes a tool to create a new project in a project management system. The tool requires a project name, a list of team member emails, and a due date. The architect wants to minimize the chance that the model provides invalid or missing arguments. Which design choice best achieves this?

Accepted Answer

Define the input schema with JSON Schema, marking all properties as required and specifying formats for email and date.. Defining a JSON Schema with required properties and format constraints (e.g., email, date) gives the model a clear contract. The MCP client can validate against this schema before invoking the tool, catching missing or malformed arguments early. This proactive constraint is more effective at minimizing invalid inputs than relying on descriptions or server-side rejection alone.

Answer

Implement server-side validation that rejects invalid requests and returns an error message to the model.

Answer

Allow any string for each parameter and let the model infer the correct format from examples in the prompt.

Answer

Provide a detailed natural language description in the tool's description field explaining each parameter.

Question 9

An architect is building a Claude-based agent that must reconcile invoice disputes. The orchestrator runs a single loop where Claude may emit several tool_use blocks in one assistant turn: one block calls lookup_invoice, another calls fetch_payment_history, and a third calls get_contract_terms. A junior developer proposes executing the first tool_use block, feeding its tool_result back to Claude, and only then deciding whether to run the other two. What is the architecturally correct way for the orchestrator to handle this turn?

Accepted Answer

Execute all tool_use blocks from the assistant turn, then return every tool_result in a single subsequent user message keyed by tool_use_id.. An assistant turn containing multiple tool_use blocks constitutes a single batched request for those tools. The orchestrator must execute each block and return all tool_result entries together in one subsequent user message, each tagged with the matching tool_use_id. This keeps the conversation structurally valid, lets independent lookups run concurrently, and minimizes model round-trips before Claude can reason over the combined evidence.

Answer

Execute the first tool_use block, return its result alone, and let Claude re-issue the remaining two calls in a fresh assistant turn.

Answer

Execute the three calls sequentially, returning each tool_result in its own separate user message as soon as that call finishes.

Answer

Skip execution of the tool_use blocks and send a natural-language summary of the assistant text so Claude can decide what to do next.

Question 10

A new engineer joins a team and clones the project repository. They run Claude Code and find it already follows the team's conventions for commit messages and test layout without any personal setup. Which explanation accounts for this?

Accepted Answer

The repository includes a project memory file that Claude Code loads automatically as context for sessions in that project.. Behavior that appears automatically in a fresh clone, with no personal configuration, points to content that is committed alongside the code and loaded as session context. A project memory file does precisely that: it is read automatically for sessions rooted in that repository and carries team conventions to every developer. Commit-history inference, synchronized user profiles, and generic built-in defaults all fail to explain consistent, team-specific behavior.

Answer

The engineer's global user settings were synchronized from a shared team profile during installation.

Answer

Claude Code ships with built-in defaults that match most enterprise conventions out of the box.

Answer

Claude Code infers the team's conventions by analyzing recent commit history at session start.

Question 11

A support agent running on the Claude Messages API must look up a customer's order status before answering. The developer writes a single request that includes the get_order_status tool definition and the user's question, then expects the model to return the order status directly in its first response. What actually happens, and what must the developer implement?

Accepted Answer

Claude returns a tool_use block requesting get_order_status; the application must execute the tool and send back a tool_result, then call the API again to get the final answer.. Tool use in the Claude Messages API is a caller-driven loop: the model emits a tool_use request, the application executes the function and returns a tool_result, and a follow-up request lets Claude produce the final answer. Because the API is stateless and never runs customer functions itself, the developer must implement this round trip.

Answer

Claude returns the order status immediately because tool definitions are executed server-side by Anthropic before the response is generated.

Answer

Claude executes the tool and returns both the tool output and its final answer in one response, so no second request is needed.

Answer

The request fails with a validation error because a tool definition cannot be supplied alongside a normal user text message.

Question 12

A developer builds a Claude-powered assistant that answers questions over a 300-page policy manual. When the whole manual is placed in a single prompt, answers to questions about clauses in the middle of the document are frequently wrong or vague, while answers about the opening and closing sections are accurate. The manual must stay available in full, and the team wants to keep latency reasonable. Which technique most effectively improves accuracy for the mid-document clauses?

Accepted Answer

Split the manual into sections, embed each section, retrieve the most relevant sections for the question, and place only those retrieved sections in the prompt before the question.. Accuracy drops for material buried in the middle of a very long context because attention is spread thin across the document. Retrieving the sections most relevant to each question and placing only those in the prompt shrinks the context to on-topic passages, which restores accuracy for mid-document clauses while the full manual stays indexed for availability. Reordering or enlarging the same long context does not fix the attention problem.

Answer

Increase max_tokens substantially and instruct the model to think step by step before answering each question.

Answer

Ask the user to restate their question using exact phrases from the manual so the model can match keywords directly.

Answer

Keep the full manual in the prompt but move it so the manual text appears after the question rather than before it.

Question 13

A team is extracting medication names and dosages from clinical notes. The notes contain many similar-looking terms, and the team needs high precision to avoid false positives. They plan to use few-shot examples. Which design of the few-shot examples best supports high precision in this scenario?

Accepted Answer

Include a mix of positive examples and carefully chosen hard negatives that resemble medications but should not be extracted.. High precision in a field with lookalike terms depends on teaching the model where the boundary lies. A mix of positive examples and hard negatives does that by showing both what to extract and what to reject. Positive-only, single-example, or random sampling designs do not surface the confusing cases, so they are less likely to reduce false positives in clinical extraction.

Answer

Provide many examples of correct extractions only, covering a wide range of medication names.

Answer

Randomly sample examples from the dataset without regard to difficulty or similarity.

Answer

Use a single detailed example and rely on the model to generalize to all other notes.

Question 14

A financial analyst uses Claude via the Messages API to extract line items from scanned invoices. The response must be valid JSON conforming to a fixed schema with fields invoice_number, date, and total. During testing, the model occasionally adds a trailing sentence after the JSON object or wraps the JSON in a markdown code fence. Which approach best guarantees the response parses cleanly while preserving extraction accuracy?

Accepted Answer

Instruct the model to begin the response with a tool_use block whose input_schema defines the invoice fields, then read the structured tool input from the response.. Constraining the response through a tool definition with an input_schema channels generation into the model's structured tool-calling pathway, so the extracted invoice fields arrive as an already-parsed object instead of free-form text. This eliminates markdown fences and trailing commentary while keeping the model focused on the document content. Prompt phrasing and sampling parameters reduce, but do not remove, format drift.

Answer

Set the max_tokens parameter to the exact length of the expected JSON string so the model cannot emit extra characters.

Answer

Request the JSON inside <output> tags and run a regular expression that captures everything between the opening and closing tags.

Answer

Append the phrase 'Return only JSON' to the end of the system prompt and set temperature to 0.0 before each request.

Question 15

An architect is standardizing Claude Code usage across a large engineering organization. They want to ensure that every developer's sessions automatically inherit a curated set of project conventions and that destructive shell commands are blocked unless explicitly approved. Which TWO configurations should the architect implement? (Choose two.)

Accepted Answer

Commit a CLAUDE.md file at the repository root containing the shared coding conventions and architectural notes. A committed CLAUDE.md at the repository root distributes shared conventions automatically to every session, and deny rules in the project's .claude/settings.json enforce hard blocks on destructive commands organization-wide. Manual per-developer setup and README-based expectations lack reliability and auditability, while blanket Bash auto-approval undermines the safety objective.

Answer

Instruct each developer to run /config and manually set the desired conventions on first launch

Answer

Enable auto-approval for all Bash commands to reduce interruptions during long sessions

Answer

Place convention notes in a README.md and expect Claude to infer them from repository files

Question 16

While working in a repository, an architect wants Claude Code to explain the purpose of a specific function in a large source file without altering any code or generating new files. Which mode should be used for this task?

Accepted Answer

Plan mode, because it prevents edits and focuses on producing an explanation or approach. Claude Code separates exploration from execution. Plan mode is the read-only posture intended for understanding code, answering questions, and outlining approaches; it will not modify files. When the goal is purely explanatory, choosing plan mode enforces the no-change requirement structurally instead of relying on the model's discretion.

Answer

Auto-accept edits mode, because approvals are bypassed and analysis proceeds faster

Answer

A new session started with the --dangerously-skip-permissions flag

Answer

Default edit mode, because Claude Code will simply describe the function without touching files

Question 17

A developer working in a monorepo wants Claude Code to follow the team's TypeScript conventions only when editing files under the `packages/api` directory, while letting other directories use different conventions. What is the most appropriate way to configure this in Claude Code?

Accepted Answer

Create a `CLAUDE.md` file inside `packages/api` containing the TypeScript conventions so Claude Code applies those instructions when working in that directory.. Claude Code discovers `CLAUDE.md` memory files by walking from the current directory up the tree, so a file placed inside `packages/api` is loaded exactly when the session operates there. This gives the API package its own TypeScript conventions while leaving sibling packages and the repository root untouched, matching the requirement for directory-scoped guidance.

Answer

Add the TypeScript conventions to the user-level `~/.claude/CLAUDE.md` file so they apply globally to every project the developer opens.

Answer

Set the `CLAUDE_CODE_MODEL` environment variable to a model fine-tuned on the API package's conventions before starting each session.

Answer

Add a `settings.json` entry with a `scope` field set to `packages/api` under the project's `.claude` directory to bind conventions to that path.

Question 18

An architect is building an MCP server that exposes a `read_file` tool. The tool's input schema currently defines `path` as a plain string. Security review requires that the tool never read outside a configured workspace root, and that the model receive a clear, machine-readable error when it attempts to do so. Which change to the tool design best satisfies this requirement?

Accepted Answer

Have the server resolve the requested path against the workspace root, reject traversal outside it, and return a structured error object.. The secure pattern is server-side enforcement plus a structured error. The MCP server should resolve the incoming path, confirm it stays within the workspace root, and return a typed error payload when it does not. That keeps the security boundary out of the model's control while still giving the model enough information to recover gracefully on the next turn.

Answer

Add a `root` parameter to the schema so the model can specify the allowed workspace root on each call.

Answer

Keep `path` as a string but document in the tool description that paths must stay inside the workspace root.

Answer

Constrain `path` in the JSON Schema with an `enum` of known filenames and reject any other value.

Question 19

You are building a customer-support agent with the Anthropic Messages API. The agent must call a `get_order_status` tool, and the result is required before it can decide whether to issue a refund. The tool sometimes takes several seconds to respond. Which approach best ensures the agent does not prematurely finalize its answer before the tool result is available?

Accepted Answer

After receiving a `tool_use` block, execute the tool and send a `user` message containing a `tool_result` block with the matching `tool_use_id` before requesting the next completion.. Tool use in the Anthropic Messages API is a multi-turn exchange: the model emits a `tool_use` block, the application executes the function, and the application returns a `tool_result` block tied to the same `tool_use_id`. The model cannot finalize a refund decision until that result is in context, so completing the round trip before the next completion is what prevents premature answers.

Answer

Use `stop_sequences` to halt generation whenever the model emits a `tool_use` block.

Answer

Set `tool_choice` to `{"type": "any"}` so the model is forced to call a tool on every turn.

Answer

Increase `max_tokens` so the model has room to wait for the tool response within the same completion.

Question 20

A developer is building a classification pipeline that routes support tickets into one of eight categories. They want Claude to return a category label and a confidence score between 0 and 1. The output must be parseable by a JSON parser without post-processing. They plan to use the Anthropic Messages API. Which approach best ensures the output is directly parseable JSON with the required fields?

Accepted Answer

Describe the JSON schema in the system prompt, prefill the assistant turn with `{`, and validate the response with a JSON parser.. Describing the schema in the system prompt gives Claude the keys and types to emit, and prefilling the assistant turn with `{` forces the response to begin as a JSON object with no preamble or markdown fence. Validating with a JSON parser catches rare deviations. Together these produce directly parseable output, unlike free-text formats, stop-sequence tricks, or high-temperature sampling.

Answer

Set `temperature` to 1 and rely on the model's creativity to produce varied but valid JSON.

Answer

Ask Claude to return the category and confidence in a single sentence like 'Category: X, Confidence: 0.9'.

Answer

Use the `stop_sequences` parameter set to '}' so Claude stops as soon as it finishes the JSON object.