diagnose-generation-failure

When SDK generation fails, diagnose the root cause and determine the fix strategy.

When to Use

• speakeasy run failed with errors
• SDK generation produced unexpected results
• User says: "generation failed", "SDK build error", "why did generation fail"

Inputs

Input	Required	Description
OpenAPI spec	Yes	Path to spec that failed generation
Error output	Helpful	Error messages from failed run

Outputs

Output	Description
Diagnosis	Root cause of failure
Fix strategy	Overlay vs spec fix vs user decision
Action items	Specific steps to resolve

Diagnosis Steps

1. Run lint to get detailed errors:

   speakeasy lint openapi --non-interactive -s <spec-path>
   

2. Categorize issues:

   • Fixable with overlays: Missing descriptions, poor operation IDs
   • Requires spec fix: Invalid schema, missing required fields
   • Requires user input: Design decisions, authentication setup

Decision Framework

Issue Type	Fix Strategy	Example
Missing operationId	Overlay	Use speakeasy suggest operation-ids
Missing description	Overlay	Add via overlay
Invalid $ref	Ask user	Broken reference needs spec fix
Circular reference	Ask user	Design decision needed
Missing security	Ask user	Auth design needed

What NOT to Do

• Do NOT disable lint rules to hide errors
• Do NOT try to fix every issue one-by-one
• Do NOT modify source spec without asking
• Do NOT assume you can fix structural problems

Troubleshooting Tree

PROBLEM
  │
  ├─ ResponseValidationError at runtime?
  │    └─ SDK types don't match server responses
  │         ├─ Run contract tests to identify mismatches
  │         └─ Fix spec or create overlay to correct types
  │
  ├─ SDK doesn't match live API behavior?
  │    ├─ Spec may have drifted from API
  │    │    → Run contract tests to detect drift
  │    └─ Third-party spec may be inaccurate
  │         → Validate with contract testing before trusting
  │
  ├─ Type mismatch errors in generated SDK?
  │    ├─ At compile time → Check spec schema definitions
  │    └─ At runtime → Server returns unexpected types
  │                    → Contract testing required
  │
  └─ Enum value not recognized?
       └─ API returned value not in spec enum
            ├─ Add missing value to spec/overlay
            └─ Or use open enums for anti-fragility

Working with Large OpenAPI Specs

Use yq (YAML) or jq (JSON) to inspect specs without loading full content:

# List all paths
yq '.paths | keys' spec.yaml

# Inspect a specific endpoint
yq '.paths["/users/{id}"]' spec.yaml

# List all schema names
yq '.components.schemas | keys' spec.yaml

# List all operationIds
yq '[.paths[][].operationId // empty] | unique' spec.yaml

Strategy Document

For complex issues, produce a document:

## OpenAPI Spec Analysis

### Blocking Issues (require user input)
- [List issues that need human decision]

### Fixable Issues (can use overlays)
- [List issues with proposed overlay fixes]

### Recommended Approach
[Your recommendation]

Related Skills

• manage-openapi-overlays - Fix issues with overlays
• setup-sdk-testing - Contract testing for validation
• writing-openapi-specs - Spec design best practices