Fen registries

Source-scanned registry entries supplied by first-party extensions: commands, tools, providers, presenters, panels, status items, and related extension surfaces.

commands

Registered slash commands.

commands registry
NameDescriptionSource
animations Toggle TUI busy animationsextensions/adapters/presenters/tui/init.fnl:697
cancel-all Cancel current turn and clear queuesextensions/behaviors/inspectors/queue/commands/queue.fnl:163
compact Summarize older context and keep recent messages in this sessionextensions/behaviors/companions/compact/init.fnl:233
docs Browse runtime docs: /docs [topic] [name]extensions/behaviors/kernel/docs/init.fnl:484
errors Toggle recent error details / tracebacksextensions/adapters/presenters/tui/init.fnl:733
expand Toggle full vs collapsed tool-result bodiesextensions/adapters/presenters/tui/init.fnl:665
extensions Pick an extension, show details, or inspect live registryextensions/behaviors/inspectors/extensions/commands/extension.fnl:494
handoff Summarize this session, seed a fresh session with the summaryextensions/behaviors/companions/handoff/init.fnl:141
help Show available commands and controlsextensions/behaviors/kernel/essentials/commands/help.fnl:94
markdown Toggle Markdown rendering of assistant textextensions/adapters/presenters/tui/init.fnl:681
mem Toggle the memory diagnostics panel; /mem gc forces a GC passextensions/behaviors/companions/mem/init.fnl:246
model Switch model (overlay if no arg; index/name/substring if given)extensions/behaviors/kernel/essentials/commands/model.fnl:121
n Alias for /newextensions/behaviors/actions/sessions/commands/session.fnl:319
new Reset the current conversation and start a fresh sessionextensions/behaviors/actions/sessions/commands/session.fnl:159
prompt Toggle the prompt-fragments panel; /prompt rendered emits the rendered promptextensions/behaviors/inspectors/prompt/commands/prompt.fnl:105
queue Toggle the queue panel; /queue clear|mode preserve their actionsextensions/behaviors/inspectors/queue/commands/queue.fnl:148
r Alias for /reloadextensions/behaviors/actions/sessions/commands/session.fnl:343
redraw Force a full terminal repaint to recover from corruptionextensions/adapters/presenters/tui/init.fnl:753
reload Hot-reload core modules and source overlaysextensions/behaviors/actions/sessions/commands/session.fnl:265
reload-extension Reload one external extension by nameextensions/behaviors/inspectors/extensions/commands/extension.fnl:464
resume Resume a session (overlay if no arg; id/prefix/path/index if given)extensions/behaviors/actions/sessions/commands/session.fnl:332
sessions Pick a recent session to resume (overlay)extensions/behaviors/actions/sessions/commands/session.fnl:326
skills Pick a skill, show details, or list discovered Agent Skillsextensions/behaviors/companions/skills/init.fnl:711
status Toggle the status panel (model, provider, tokens, session)extensions/behaviors/inspectors/status/commands/status.fnl:157
thinking Show/set thinking effort; /thinking blocks on|off toggles displayextensions/behaviors/kernel/essentials/commands/thinking.fnl:115
thinking-blocks Show or hide assistant thinking blocksextensions/adapters/presenters/tui/init.fnl:714
todos Toggle the todo panel; /todos show prints the current listextensions/behaviors/companions/todo/init.fnl:305

tools

Registered agent tools.

tools registry
NameDescriptionSource
agent_state Read structured state of the running agent. Read-only; does not evaluate code. Query is a tiny Fennel-shaped data language. Examples: (:get :model), (:get :thinking), (:count (:get :messages)), (:get :messages -1), (:pluck (:get :tools) :name), (:get :extensions :panels), (:where (:get :messages) :role :assistant), (:last (:where (:get :messages) :role :assistant)), (:slice (:get :messages) -5 5), (:keys (:get)). Prefer narrow queries over dumping large roots. Output defaults to JSON; use format=fennel for Fennel rendering when available.extensions/behaviors/companions/agent-state/init.fnl:13
builtin-tool-registry Dynamic loop registering every built-in tool spec from the builtin tools registry.extensions/behaviors/kernel/builtin-tools/init.fnl:17
fen_docs Read or search fen runtime docs and extension contracts. Useful for implementing extensions: inspect register kinds, canonical types, event shapes, and live commands/tools/providers. Topics: topics, commands, tools, providers, auth-backends, session-backends, presenters, controls, status, panels, prompt-fragments, introspectors, events, types, register-kinds, interfaces, extensions. Use name for a specific entry, e.g. {topic:'register-kinds', name:'tool'} or {topic:'types', name:'ToolResultMessage'}. Use query to search docs, optionally scoped by topic.extensions/behaviors/kernel/docs/init.fnl:506
todo_write Create or update the structured todo list for this session. Use for non-trivial multi-step work. This tool overwrites the full current list; provide every item that should remain. Status must be pending, in_progress, or completed, with at most one in_progress item. Use an empty items array to clear the list.extensions/behaviors/companions/todo/init.fnl:289

providers

Registered LLM providers.

providers registry
NameDescriptionSource
anthropic Anthropic Messages provider using ANTHROPIC_API_KEY and the default claude-haiku-4-5 model.extensions/adapters/providers/anthropic/init.fnl:20
openai OpenAI Chat Completions provider using OPENAI_API_KEY and the default gpt-5.4-nano model.extensions/adapters/providers/openai/init.fnl:44
openai-codex ChatGPT subscription/Codex Responses provider using the openai-codex OAuth auth backend and default gpt-5.5 model.extensions/adapters/providers/openai/init.fnl:66
openai-responses OpenAI Responses API provider using OPENAI_API_KEY and the default gpt-5.4-nano model.extensions/adapters/providers/openai/init.fnl:50

auth-backends

Registered auth backends.

auth-backends registry
NameDescriptionSource
openai-codex ChatGPT subscription PKCE OAuth credentials stored in fen's auth.json.extensions/adapters/providers/openai/init.fnl:54

session-backends

Registered session persistence backends.

session-backends registry
NameDescriptionSource
jsonl Append-only JSONL session backend under XDG state. Records canonical messages, replayable via --continue / /resume.extensions/adapters/session-backends/jsonl/init.fnl:9

presenters

Registered interactive presenters.

presenters registry
NameDescriptionSource
print Registered print presenter.extensions/adapters/presenters/print/init.fnl:34
stdio Registered stdio presenter.extensions/adapters/presenters/stdio/init.fnl:281
tui Registered tui presenter.extensions/adapters/presenters/tui/init.fnl:601
web Registered web presenter.extensions/adapters/presenters/web/init.fnl:170

controls

Registered keyboard/UI controls.

controls registry
NameDescriptionSource
hard-refresh Redraw the screen / recover from terminal corruptionextensions/adapters/presenters/tui/init.fnl:653
jump-to-live-bottom Jump to the live bottom and resume following transcript outputextensions/adapters/presenters/tui/init.fnl:629
jump-to-user-message Jump to the latest user message; repeat for previous messagesextensions/adapters/presenters/tui/init.fnl:623
quit Quit; ctrl-c also clears input or cancels a busy turnextensions/adapters/presenters/tui/init.fnl:647
suspend Suspend to the shell (resume with fg)extensions/adapters/presenters/tui/init.fnl:659
toggle-thinking-blocks Toggle thinking blocksextensions/adapters/presenters/tui/init.fnl:641
toggle-tool-results Toggle tool-result bodiesextensions/adapters/presenters/tui/init.fnl:635

status

Registered status-line items.

status registry
NameDescriptionSource
attention Registered attention status-line item.extensions/adapters/presenters/tui/init.fnl:553
attention Registered attention status-line item.extensions/adapters/presenters/web/init.fnl:153
context Registered context status-line item.extensions/adapters/presenters/tui/init.fnl:524
context Registered context status-line item.extensions/adapters/presenters/web/init.fnl:124
follow-up-queue Registered follow-up-queue status-line item.extensions/adapters/presenters/tui/init.fnl:543
follow-up-queue Registered follow-up-queue status-line item.extensions/adapters/presenters/web/init.fnl:143
model Registered model status-line item.extensions/adapters/presenters/web/init.fnl:115
model Registered model status-line item.extensions/adapters/presenters/tui/init.fnl:506
scroll Registered scroll status-line item.extensions/adapters/presenters/tui/init.fnl:564
steering-queue Registered steering-queue status-line item.extensions/adapters/presenters/tui/init.fnl:533
steering-queue Registered steering-queue status-line item.extensions/adapters/presenters/web/init.fnl:133
thinking Registered thinking status-line item.extensions/adapters/presenters/tui/init.fnl:515
todo Registered todo status-line item.extensions/behaviors/companions/todo/init.fnl:312
version Registered version status-line item.extensions/adapters/presenters/tui/init.fnl:574

panels

Registered presenter panels.

panels registry
NameDescriptionSource
(dynamic) Registered (dynamic) panel registry entry.extensions/behaviors/companions/todo/init.fnl:311
busy TUI busy-state panel showing spinner, retry information, and current turn elapsed time.extensions/adapters/presenters/tui/init.fnl:593
busy Web presenter spinner row shown while the agent is busy.extensions/adapters/presenters/web/init.fnl:162
docs Runtime documentation browser panel backing the /docs command and fen_docs tool.extensions/behaviors/kernel/docs/init.fnl:526
errors TUI error introspection panel showing recent error summaries and traceback details.extensions/adapters/presenters/tui/init.fnl:589
extensions Extension detail and picker panel backing the /extensions command.extensions/behaviors/inspectors/extensions/commands/extension.fnl:510
mem Memory diagnostics panel backing the /mem command and heap history display.extensions/behaviors/companions/mem/init.fnl:260
prompt Prompt-fragment inspection panel backing the /prompt command.extensions/behaviors/inspectors/prompt/commands/prompt.fnl:118
queue Queued follow-up/cancel-all panel backing queue-management commands.extensions/behaviors/inspectors/queue/commands/queue.fnl:180
skills Skill picker/detail panel backing the /skills command.extensions/behaviors/companions/skills/init.fnl:733
status Runtime status details panel backing the /status command.extensions/behaviors/inspectors/status/commands/status.fnl:167

prompt-fragments

Registered system-prompt fragments.

No source-scanned registrations.

extensions

First-party extension manifests.

extensions registry
NameDescriptionSource
agent_state Read-only introspection tool for the running agentextensions/behaviors/companions/agent-state/manifest.fnl:1
builtin_tools Built-in fen tools: bash, read, write, ls, edit, grep, find.extensions/behaviors/kernel/builtin-tools/manifest.fnl:1
compact Context compaction command: summarize older messages and keep recent context.extensions/behaviors/companions/compact/manifest.fnl:1
default_prompt First-party default system prompt policyextensions/behaviors/kernel/default-prompt/manifest.fnl:1
docs In-agent runtime documentation browserextensions/behaviors/kernel/docs/manifest.fnl:1
essentials Essential fen slash commands: help and model selection.extensions/behaviors/kernel/essentials/manifest.fnl:1
extensions_inspector Extension inspector: /extensions, /reload-extension, and extension detail panel.extensions/behaviors/inspectors/extensions/manifest.fnl:1
handoff Session handoff command: summarize current context and seed a fresh session.extensions/behaviors/companions/handoff/manifest.fnl:1
mem Runtime memory diagnostics commandextensions/behaviors/companions/mem/manifest.fnl:1
print One-shot stdout presenter for --printextensions/adapters/presenters/print/manifest.fnl:1
prompt Prompt inspector: /prompt command and prompt-fragment panel.extensions/behaviors/inspectors/prompt/manifest.fnl:1
provider_anthropic First-party Anthropic Messages provider.extensions/adapters/providers/anthropic/manifest.fnl:1
provider_openai First-party OpenAI provider family (Chat Completions, Responses, Codex subscription, and Codex OAuth auth).extensions/adapters/providers/openai/manifest.fnl:1
queue Queue inspector: /queue, /cancel-all, and queue panel.extensions/behaviors/inspectors/queue/manifest.fnl:1
session_jsonl JSONL session backendextensions/adapters/session-backends/jsonl/manifest.fnl:1
sessions Conversation and session lifecycle commands: new, reload, sessions, resume, and aliases.extensions/behaviors/actions/sessions/manifest.fnl:1
skills Agent Skills discovery and prompt fragmentextensions/behaviors/companions/skills/manifest.fnl:1
status Runtime status inspector: /status command and status panel.extensions/behaviors/inspectors/status/manifest.fnl:1
stdio Line-mode stdin/stdout presenterextensions/adapters/presenters/stdio/manifest.fnl:1
todo Structured todo list companion tool, panel, and status itemextensions/behaviors/companions/todo/manifest.fnl:1
tui First-party termbox2 presenterextensions/adapters/presenters/tui/manifest.fnl:1
web First-party LuaSocket/SSE browser presenterextensions/adapters/presenters/web/manifest.fnl:1