Template Reference

The bodies of the files you author for Polytoken (facets, subagents, and skills) are templates. The front-matter schema for each file type is at the bottom of the page.

Templates catch typos at render time: referencing a variable that does not exist raises an error rather than rendering blank, so a broken prompt never reaches the model. Guard optional values with the functions below or with a conditional.

Variables

Model

Variable	Type	Holds
model_name	string	The active model’s name.
model_variant	string	The model family, for example claude, openai, or gemini.
model_id	string	The provider the model runs through, for example anthropic or openai.
max_tool_batch_size	number	How many counted tool calls the model may issue in one turn.
supports_vision	boolean	Whether the model accepts images.
can_read_images	boolean	Whether image reading is turned on for this model.

Environment and session

Variable	Type	Holds
facet_name	string	The active facet’s name. Absent in a subagent template.
subagent_name	string	The subagent’s name. Present only in a subagent template.
project_path	string	The project’s root directory.
cwd	string	The current working directory.
session_id	string	The current session’s identifier.
current_date	string	Today’s date.
is_non_interactive	boolean	Whether the current run has no human in the loop.
prompt	string	The prompt that started this turn. Absent in an AGENTS.md template.

What is available

Variable	Type	Holds
available_tools	list	The names of every tool the model can use this turn.
available_undeferred_tools	list	The tools whose full definitions Polytoken includes in the prompt this turn.
available_deferred_tools	list	The tools the model reaches through tool search.
tool_library	list	Each tool, with its name, description, and an example.
available_mcp_servers	list	The names of the connected MCP servers.
available_subagents	list	Each subagent, with its name and description.
available_skills	list	Each skill, with its name and description.

Project and session metadata

Variable	Type	Holds
project_metadata	object	Whatever you set as project metadata, passed through untyped.
auto_drain_notifications	boolean	Whether Polytoken delivers finished background work as soon as it is ready.

The per-row notes above mark which variables a given template omits.

Functions

These functions are available in every template:

Function	Returns	Effect
has_tool(name)	boolean	Whether a tool with that name is available this turn.
get_tool(name)	object	The named tool’s library entry, or an empty object if the tool is unavailable.
has_mcp(name)	boolean	Whether an MCP server with that name is connected.
is_model_variant(variant)	boolean	Whether the active model belongs to that family.
has_skill(name)	boolean	Whether a skill with that name is available.

One function is available only in a facet template, because a facet composes the system prompt:

Function	Returns	Effect
transclude(uri)	string	Includes one of Polytoken’s shipped prompt fragments by its polytoken:// address.

Front-matter schemas

The front matter of each authored file type has its own set of legal keys.

Facet front matter

# TODO: add generated facet front-matter schema here.

Subagent front matter

# TODO: add generated subagent front-matter schema here.

Skill front matter

# TODO: add generated skill front-matter schema here.