A method implemented by one or more processors, the method comprising: receiving a request for an automated assistant to initialize performance of an action, wherein the automated assistant is accessible via an automated assistant interface of a client device (104; 210; 516) that is in communication with a display device and a sensor, and wherein the sensor provides an output indicative of a distance of a user (102; 208) relative to the display device, wherein the user and one or more additional users are in an environment with the client device; determining that the user is a currently active user of the automated assistant; determining, based on the output of the sensor, a distance measure corresponding to an estimated distance of the user relative to the display device, wherein determining the distance measure corresponding to the estimated distance of the user comprises determining the distance measure of the user, in lieu of the one or more additional users, in response to determining that the user is the currently active user of the automated assistant; identifying, based on the received request, an agent for completing the action, wherein the agent is accessible to the automated assistant and is configured to provide content items for the client device based on the estimated distance of the user relative to the display device; in response to receiving the request and identifying the agent based on the received request, generating an agent request for the identified agent to provide content items in furtherance of the action, wherein the agent request identifies the determined distance measure; transmitting the agent request to the agent to cause the agent to select a subset of content items for the action based on a correspondence between the subset of candidate content items and the distance measure included in the agent request, wherein the subset of the candidate content items is configured to be rendered at the client device uniquely, relative to other content items excluded from the subset of content items; and causing the client device to render the selected subset of candidate content items. receiving a request for an automated assistant to initialize performance of an action, wherein the automated assistant is accessible via an automated assistant interface of a client device (104; 210; 516) that is in communication with a display device and a sensor, and wherein the sensor provides an output indicative of a distance of a user (102; 208) relative to the display device, wherein the user and one or more additional users are in an environment with the client device; determining that the user is a currently active user of the automated assistant; determining, based on the output of the sensor, a distance measure corresponding to an estimated distance of the user relative to the display device, wherein determining the distance measure corresponding to the estimated distance of the user comprises determining the distance measure of the user, in lieu of the one or more additional users, in response to determining that the user is the currently active user of the automated assistant; identifying, based on the received request, an agent for completing the action, wherein the agent is accessible to the automated assistant and is configured to provide content items for the client device based on the estimated distance of the user relative to the display device; in response to receiving the request and identifying the agent based on the received request, generating an agent request for the identified agent to provide content items in furtherance of the action, wherein the agent request identifies the determined distance measure; transmitting the agent request to the agent to cause the agent to select a subset of content items for the action based on a correspondence between the subset of candidate content items and the distance measure included in the agent request, wherein the subset of the candidate content items is configured to be rendered at the client device uniquely, relative to other content items excluded from the subset of content items; and causing the client device to render the selected subset of candidate content items.