Skip to main content
Glama
RhombusSystems

Rhombus MCP Server

Official

faces-tool

Retrieve face events to identify who was seen at a location. Search registered faces by name or label, with automatic name resolution and time/location filters.

Instructions

This tool interacts with the Rhombus face recognition system to retrieve information about face sightings and registered faces.

If the user is asking about how many people were seen (head count / occupancy), use the report-tool with GET_OCCUPANCY_ENABLED_CAMERAS and GET_OCCUPANCY_COUNT_REPORT instead. This tool (faces-tool) is best for identifying who was seen (unique individuals by name), and its face count data is also automatically included in report-tool people-counting responses via the faceCountEnrichment field.

Important for person-presence questions: When asked whether specific people were seen or are present, you should ALSO call events-tool with eventType "access-control" to check badge-in records. Face recognition and access control are complementary — someone may badge in without face recognition triggering, or be seen by a camera without badging in.

If the requestType is "get-face-events":

  • Use this tool to answer questions about face sightings, including questions like "who was in the office" or "who was seen today". Can be used for reporting, to generate a report on who was seen by the camera system.

  • Automatic name resolution: You can pass partial or first-name-only names in faceNames (e.g., "Brandon", "Omar"). The tool automatically looks up the registered faces directory and resolves them to exact names and person UUIDs before searching. Check the "resolvedNames" field in the response to see what each queried name was matched to (null means no match found).

  • You can filter face events using parameters like 'faceNames', 'hasEmbedding', 'hasName', 'labels', 'locationUuids', 'personUuids', and a time range using 'rangeStart' and 'rangeEnd' (timestamps in milliseconds).

  • If you'd like to know about all face events at a location, pass in a location UUID and no device UUIDs. This will correctly return all face events at that location.

  • When the user asks about a specific person at a location (e.g. "Jane Doe at Main Office"), call get-registered-faces first to get the list of registered names, find the best match, then call get-face-events with that precise name. The tool expects precise names as stored in the system.

  • When querying faces at a location, pass only the location UUID in searchFilter; do not pass device UUIDs in searchFilter.deviceUuids, so the API returns all faces detected at that location.

If the requestType is "get-registered-faces":

  • This tool retrieves a list of all people (registered faces) currently known to the Rhombus system for your organization. This list includes information about each registered person, including their assigned labels.

  • This returns ALL people registered in the system, regardless of the provided timestampFilter.

  • Each person in the response includes a "labels" array showing which label groups they belong to (e.g., "Engineering", "Visitors"). Use these labels to answer questions about groups of people.

If the requestType is "get-person-labels":

  • This retrieves a mapping of all person UUIDs to their assigned labels across the organization.

  • Use this to discover what label groups exist and which registered faces belong to each group.

  • Useful when the user asks about a group (e.g., "was anyone from Engineering seen today?") — get the labels first, find the person UUIDs for that label, then query face events filtered by those personUuids or labels.

Output filtering (all tools):

  • includeFields (string[]): Dot-notation paths to keep in the response (e.g. "vehicleEvents.vehicleLicensePlate"). Omit to return all fields.

  • filterBy (array): Predicates to filter array items. Each entry: {field, op, value} where op is one of = != > >= < <= contains. All conditions are ANDed. Example: [{field:"vehicleLicensePlate", op:"=", value:"ABC123"}] WARNING: some tool responses exceed 400k characters — use these params to request only the data you need.

Input Schema

TableJSON Schema
NameRequiredDescriptionDefault
requestTypeYes
faceEventFilterYes
timeZoneYesThe timezone for formatting timestamps which should come from the location of the camera for the face event. This is necessary for the tool to produce accurate formatted timestamps.
faceEventUuidYesUUID of a face event to search similar faces from. Required for 'search-similar-faces'.
personUuidYesUUID of a person to get face events for. Required for 'get-face-events-by-person'.
includeFieldsYesDot-notation field paths to include in the response (e.g. "vehicleEvents.vehicleLicensePlate"). Pass null to return all fields. WARNING: some responses can exceed 400k characters — use includeFields to request only the data you need. For high-volume tools this may be required to get a complete answer.
filterByYesFilter array items in the response by field values. All conditions are ANDed. Example: [{field: "vehicleLicensePlate", op: "=", value: "ABC123"}, {field: "confidence", op: ">", value: 0.8}] Use alongside includeFields to get only the specific records and fields you need.

Output Schema

TableJSON Schema
NameRequiredDescriptionDefault
requestTypeYes
getFaceEventsResponseNoA list of all people seen over the given time period.
getSavedFacesResponseNoA list of all people (registered faces) currently known to the Rhombus system for your organization.
getPersonLabelsResponseNoA map of person UUIDs to their assigned label arrays. Use this to discover what label groups exist and which people belong to them.
resolvedNamesNoWhen faceNames are provided in a get-face-events request, this shows how each queried name was automatically resolved to a registered face. Key is the queried name (e.g., 'Brandon'), value is the matched registered name (e.g., 'Brandon Salzberg') or null if no match was found. Use these resolved names when reporting results to the user.
similarFaceEventsNoSimilar face event results
faceMatchmakersNoFace matchmaker records
personFaceEventsNoFace events for a specific person
lastEvaluatedKeyNoFor paginated requests, this is the returned last evaluated key that can be passed back in on the next request to get the next page of results
errorNo
Behavior4/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden. It explains automatic name resolution, filtering behavior, large response warnings, and the faceEventFilter scope. However, it does not explicitly state if the tool is read-only or mention any rate limits. Overall, it adds significant behavioral context beyond the schema.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness3/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is well-structured with headings for each requestType and output filtering, but it is verbose and contains some repetition (e.g., location UUID advice appears twice). It could be more concise while retaining clarity.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness5/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's complexity (7 parameters, multiple requestTypes, nested objects, and an output schema), the description is comprehensive. It covers all requestType behaviors, sibling tool relationships, parameter usage, and response size warnings. The presence of an output schema does not detract from the description's completeness.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters5/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 71%, but the description adds substantial value: it explains automatic name resolution for faceNames, precedence of faceNameContains, default time range of 7 days, and the use of includeFields/filterBy to manage large responses. It also clarifies that searchFilter only applies to get-face-events. This enhances understanding beyond the schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose5/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states the tool's purpose: interacting with the Rhombus face recognition system to retrieve face sightings and registered faces. It distinguishes itself from sibling tools like report-tool (for head count) and events-tool (for access control), and provides specific usage for each requestType.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines5/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description explicitly states when to use this tool vs alternatives, e.g., 'If the user is asking about how many people were seen, use the report-tool' and 'When asked whether specific people were seen... also call events-tool'. It provides clear context and exclusions.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.

Install Server

Other Tools

Latest Blog Posts

MCP directory API

We provide all the information about MCP servers via our MCP API.

curl -X GET 'https://glama.ai/api/mcp/v1/servers/RhombusSystems/rhombus-node-mcp'

If you have feedback or need assistance with the MCP directory API, please join our Discord server