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`TOKEN_REVOKED`	No	OAuth token was revoked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_ORG`	Yes	Per-org rate limit exceeded (details)
`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

See Error Handling for recovery patterns covering all 18 error codes.