Tools Overview
FieldMCP exposes 11 MCP tools across 3 providers. All tools are read-only and idempotent — they never modify data.
Response Format
Every tool returns a JSON response with this structure:
Success
{
"error": false,
"data": { ... },
"dataQuality": "COMPLETE",
"missingData": []
}Error
{
"error": true,
"code": "FIELD_NOT_FOUND",
"message": "Field 'abc' not found in organization '123'",
"retryable": false,
"suggestedAction": "Verify the field ID using deere_list_resources"
}Data Quality
Many tools return a dataQuality indicator:
| Level | Meaning |
|---|---|
COMPLETE | All data present, full confidence in results |
PARTIAL | Some optional data missing, results still valid but may be less precise |
INSUFFICIENT | Critical data missing, results may be unreliable |
Error Codes
Validation
| Code | Retryable | Description |
|---|---|---|
MISSING_REQUIRED_PARAM | No | A required parameter was not provided |
INVALID_PARAM_VALUE | No | A parameter has an invalid value |
INVALID_PARAM_TYPE | No | A parameter has the wrong type |
Authentication
| Code | Retryable | Description |
|---|---|---|
TOKEN_EXPIRED | No | OAuth token expired — farmer needs to re-authorize |
TOKEN_REVOKED | No | OAuth token was revoked |
PROVIDER_NOT_CONNECTED | No | Farmer hasn't connected this provider |
Rate Limiting
| Code | Retryable | Description |
|---|---|---|
RATE_LIMIT_USER | Yes | Per-user rate limit exceeded |
RATE_LIMIT_PROVIDER | Yes | Provider's rate limit exceeded |
Provider
| Code | Retryable | Description |
|---|---|---|
PROVIDER_UNAVAILABLE | Yes | Provider API is down (~30s retry) |
PROVIDER_TIMEOUT | Yes | Provider API timed out |
PROVIDER_ERROR | Depends | Generic provider error (5xx retryable, 4xx not) |
Resource
| Code | Retryable | Description |
|---|---|---|
RESOURCE_NOT_FOUND | No | Requested resource doesn't exist |
FIELD_NOT_FOUND | No | Field doesn't exist |
ORG_NOT_FOUND | No | Organization doesn't exist |
EQUIPMENT_NOT_FOUND | No | Equipment doesn't exist |
Providers
- John Deere — List resources, field overviews, equipment status, operation search
- Farm Intelligence — Field diagnosis, yield analysis, field comparison, action plans, rule lookup
- Weather — Historical and forecast weather with GDD, precipitation, temperature