[WRITE] Check that the stored login of a server for a Docker registry still works (Coolify v4.4+). Changes nothing, but the API requires write ability.
[WRITE] Check that the stored login of a server for a Docker registry still works (Coolify v4.4+). Changes nothing, but the API requires write ability.
| Name | Required | Description | Default |
|---|---|---|---|
| uuid | Yes | UUID of the server | |
| registry | Yes | Registry host without scheme or path, e.g. ghcr.io or docker.io |
Changes observed during successful MCP inspections.
v4.3.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the burden and does well: it flags the [WRITE] classification and explains the non-obvious reason ('Changes nothing, but the API requires write ability'), preventing an agent from assuming this mutates state. It falls short of describing what the call returns or how a failed check surfaces.
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?
The [WRITE] tag and the core purpose are front-loaded, and every clause (version requirement, non-mutating reassurance) adds information. No filler.
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 two-parameter validation call with no output schema, the description covers purpose, side-effect profile and version gating. It omits what a successful versus failed check yields, which is the one gap an agent would still want closed.
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%, with the registry parameter carrying a format example ('ghcr.io or docker.io'). The description adds nothing beyond the schema, so baseline 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 ('Check') and precise resource ('the stored login of a server for a Docker registry'), plus a version constraint (v4.4+). It is distinguishable from login/logout/list siblings by implication, but never names them explicitly.
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?
The phrasing 'still works' implies this is a validation step after a login has been stored, but the description never states when to call it versus coolify_login_server_registry or coolify_list_server_registries, nor any prerequisite that a registry entry must already exist.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.