CCDV-F Agents and the Agent SDK Practice Question
Exhibit
Error: '400 Bad Request: Tool use failed: Invalid schema definition.'
Refer to the exhibit. Which step should you take first to resolve this tool invocation error?
⚠ Common exam trap
Test-takers frequently assume they need to rewrite the entire application code or debug the model's weights instead of inspecting and validating the JSON schema format.
Answer choices
Why each option matters
Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.
Correct answer & explanation
✓
Validate the tool schema against standard JSON Schema specifications.
When encountering a schema error, validating the JSON against a strict JSON Schema standard is the most effective first step. Many errors stem from subtle syntax mistakes like missing commas, incorrect types, or invalid property names. Using a linter or schema validator ensures that the tool definition matches the requirements expected by the Anthropic SDK, which is essential for successful API calls.
Answer analysis
Option-by-option breakdown
For each option: why learners choose it and why it is or isn't the right answer here.
- ✗
Increase the temperature setting of the model.
Why it's wrong here
Temperature settings control the randomness of the model's output generation. They have no impact on the validity of the tool schema definition, which is a static configuration provided to the API before the model even begins generating its response.
- ✓
Validate the tool schema against standard JSON Schema specifications.
Why this is correct
The SDK requires tools to be defined as valid JSON Schema objects. Errors in this definition prevent the API from parsing the tool. Validating against the standard specification catches syntax issues that are often the root cause of '400 Bad Request' errors.
- ✗
Retry the request with a smaller context window.
Why it's wrong here
Context window limits affect the content of the conversation, not the structural validity of the tool definitions. Retrying will not resolve a schema syntax error, as the definition remains invalid regardless of the amount of text in the prompt or conversation history.
- ✗
Update the system prompt to be more descriptive.
Why it's wrong here
A more descriptive system prompt will not fix a technical schema error in the tool definition. The API error indicates the schema is malformed at the structural level; modifying the natural language instructions will not correct the underlying JSON syntax.
Visual reference
About these practice questions
This CCDV-F question is part of Courseiva's 257-question bank — original exam-style content with full explanations and wrong-answer analysis, never real exam questions or exam dumps. Learn why practice questions differ from exam dumps →
JA
Written and reviewed by Johnson Ajibi, MSc IT Security
Senior Network & Security Engineer · founder of Courseiva
Last reviewed September 2026 · checked against the official Anthropic exam blueprint
This CCDV-F practice question is part of Courseiva's free Anthropic certification practice question bank. Courseiva provides original exam-style practice questions with explanations, topic-based practice, mock exams, readiness tracking, and study analytics to help learners prepare for the CCDV-F exam.