Modify an existing Dynamics 365 CRM record by providing its entity set, GUID, and updated key-value data.
Update an existing entity record in Dynamics 365
| Name | Required | Description | Default |
|---|---|---|---|
| data | Yes | The data to update as key-value pairs | |
| entityId | Yes | The unique identifier (GUID) of the entity record to update | |
| entitySet | Yes | Entity set name (plural form, e.g., "contacts", "accounts", "opportunities") |
Changes observed during successful MCP inspections.
v2.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are supplied, so the description carries the full behavioral burden for a mutation operation. It says nothing about partial vs. full update semantics (i.e., whether omitted fields are cleared), optimistic concurrency/ETag requirements, permission needs, or what the response contains.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
A single short sentence with the operation front-loaded and no wasted words. Its brevity is efficient, though it comes at the cost of the behavioral detail noted elsewhere.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
For a mutation tool with no annotations, no output schema, and a nested data object, the description is thin: it omits update semantics, required field expectations, and result shape. The schema covers parameter naming but not the behavior an agent needs before writing to Dynamics 365.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema description coverage is 100%, so entitySet, entityId, and data are all documented in the schema itself. The description adds no further parameter meaning, such as which keys the data object accepts, so the baseline of 3 applies.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb (Update) and resource (an existing entity record in Dynamics 365), so an agent knows the operation is a mutation of an existing record. It does not differentiate itself from siblings like create_entity or delete_entity beyond the verb, but those are self-evidently distinct.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
No guidance on when to use this versus create_entity, delete_entity, or execute_odata_query. There is also no mention of prerequisites such as needing the record GUID or the entity set name, though the schema requires both.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.