Mc-agent-toolkit connection-auth-rules

Build a Connection Auth Rules for a Monte Carlo connection type. Fetches live connector schemas and transform steps from the apollo-agent repo.

install
source · Clone the upstream repo
git clone https://github.com/monte-carlo-data/mc-agent-toolkit
Claude Code · Install into ~/.claude/skills/
T=$(mktemp -d) && git clone --depth=1 https://github.com/monte-carlo-data/mc-agent-toolkit "$T" && mkdir -p ~/.claude/skills && cp -r "$T/skills/connection-auth-rules" ~/.claude/skills/monte-carlo-data-mc-agent-toolkit-connection-auth-rules && rm -rf "$T"
manifest: skills/connection-auth-rules/SKILL.md
source content

Connection Auth Rules Builder

Use this skill when the user wants to build a Connection Auth Rules (stored as

ctp_config
) for a Monte Carlo connection. The config is stored on the
Connection
object in the monolith and tells the Apollo agent how to transform flat credentials into the driver-specific
connect_args
format.

When to activate this skill

Activate when the user:

  • Asks to create, build, or generate a Connection Auth Rules
  • Asks what fields are needed for a connection type's Connection Auth Rules
  • Wants to customize credential transformation for a connection
  • Asks about
    MapperConfig
    ,
    TransformStep
    , or
    CtpConfig
  • Says things like "help me write Connection Auth Rules for X", "what's the connection auth rules format for X"

When NOT to activate this skill

Do not activate when the user is:

  • Creating monitors (use the monitor-creation skill)
  • Investigating data incidents (use the analyze-root-cause skill)
  • Setting up a connection in the UI (this skill builds the JSON config, not UI flows)

Step 1 — List available connection types

Locate the companion script with Bash:

find -L ~/.claude . -name fetch_schema.py -path "*/connection-auth-rules/*" 2>/dev/null | head -1

Then run it:

python3 <script_path> --list

The script outputs JSON. Parse

result.connectors
— each entry has a
name
field. Present the names to the user and ask which connection type they want to build a config for.

If the script fails: Show the error output and offer to retry. Do not proceed until you have the connector list.


Step 2 — Fetch the connector schema

Once the user selects a connection type, run the script with that connector name:

python3 <script_path> --connector <name>

The script outputs JSON. Parse

result.schema
:

  • output_keys
    — the driver-level
    connect_args
    keys the mapper must produce (from the connector's
    TypedDict
    )
  • default_field_map
    — the existing default mapping (credential field → Jinja2 template)
  • default_steps
    — any default transform steps already configured

Present a summary to the user:

  • The output keys
  • The default mapper field_map entries
  • Any existing steps with their types

Step 3 — Optionally fetch available transform steps

If the connector's default config (from Step 2) already includes steps, or if the user indicates they need custom transform steps, run:

python3 <script_path> --connector <name> --transforms

Parse

result.transforms
— each entry has:

  • name
    — the step type string used in
    "type"
  • step_input
    — fields the step reads from the pipeline state
  • step_output
    — derived fields the step writes, referenceable as
    {{ derived.<key> }}
    in the mapper
  • step_field_map
    — typical mapper entry to wire the step's output into
    connect_args

Present the available steps with their full contracts (input, output, and field_map hint).

If the script fails: Tell the user and offer to retry. You can continue without step data — just describe steps as unknown and ask the user to specify them manually.


Step 4 — Build the mapper

Walk the user through each output key in the TypedDict:

  1. Show the default template from the connector's
    MapperConfig
    (if one exists).
  2. Ask if they want to keep the default or customize it.
  3. For custom values, help the user write a Jinja2 template expression.

Jinja2 template help

The template context has two namespaces:

  • raw
    — the flat credential dict as received. Use
    {{ raw.field_name }}
    to reference a credential field directly. Example:
    {{ raw.client_id }}
  • derived
    — fields added by transform steps. Use
    {{ derived.field_name }}
    to reference a step's output. Example:
    {{ derived.private_key_pem }}

Common patterns:

  • Simple field reference:
    "{{ raw.username }}"
  • Conditional/default:
    "{{ raw.port | default('1433') }}"
  • Concatenation:
    "{{ raw.host }}:{{ raw.port }}"

When the user doesn't know their credential field names, remind them these come from the Data Collector's credential dict — the keys are whatever the DC sends for that connection type.


Step 5 — Configure transform steps (optional)

If the connector needs steps (e.g. decoding a PEM certificate, constructing a derived field), help the user configure each step. A step dict has these fields:

FieldRequiredDescription
type
yesStep type name (e.g.
"load_private_key"
)
input
yesDict of template strings the step reads (e.g.
{"pem": "{{ raw.private_key_pem }}"}
)
output
yesDict mapping the step's logical output names to derived key names (e.g.
{"private_key": "private_key_der"}
)
when
noJinja2 boolean expression — step only runs if this evaluates to true (e.g.
"raw.ssl_ca_pem is defined"
)
field_map
noMapper entries contributed only when this step runs — useful for conditional fields

Walk the user through

type
,
input
, and
output
for each step. Ask about
when
if the step should only run under certain credential conditions (e.g. when an optional SSL cert is present).

Steps run in order before the mapper. The mapper can reference step outputs via

{{ derived.<key> }}
.


Step 6 — Output the final config

Produce the complete Connection Auth Rules as a Python dict (ready to serialize to JSON for storage). This is stored as

ctp_config
on the
Connection
model:

{
    "steps": [
        # each step as a dict, e.g.:
        {
            "type": "load_private_key",
            "input": {
                "pem": "{{ raw.private_key_pem }}"
            },
            "output": {
                "private_key": "private_key_der"
            }
            # optional: "when": "raw.private_key_pem is defined"
        }
    ],
    "mapper": {
        "field_map": {
            "output_key": "{{ raw.credential_field }}",
            # step output referenced as: "private_key": "{{ derived.private_key_der }}"
            # ...
        }
    }
}

Also show the equivalent JSON, since this is what gets stored in the monolith's

Connection.ctp_config
field and entered in the "Connection auth rules" field in the UI.

Remind the user that validation happens server-side via

validateConnectionCtpConfig
— they should test the config through that mutation (or the Validate button in the UI) after saving it.


Notes

  • No in-skill validation. The skill helps construct the config but does not execute or validate it. The user validates via the monolith's
    validateConnectionCtpConfig
    GraphQL mutation or the Validate button in the "Connection auth rules" UI section.
  • is not None
    pattern.
    An empty
    field_map
    (
    {}
    ) is valid — do not treat it as missing. The monolith checks
    ctp_config is not None
    , not truthiness.
  • Steps are optional. Most simple connectors use
    steps: []
    . Only add steps when the user needs credential transformation (e.g. PEM decoding, composite field construction).
  • Fetch failures are recoverable. If the GitHub API fetch fails, tell the user exactly what failed and offer to retry. Do not silently fall back to guessed schemas.
  • Naming: The user-facing name for this feature is "Connection auth rules". The underlying field and backend model remain
    ctp_config
    /
    CtpConfig
    .