tools: a non-admin may reach their own session directory ...

A non-admin was confined to user_data/<user_id>/ alone, which made four
tools reject the directory the user's own uploads land in: share_file
refused the file it was asked to send back, filesystem could not read it,
and terminal/code_exec could not be pointed at it. In a prod session the
agent worked around the refusal by copying the uploaded file into its
sandbox with code_exec — the very bypass the injected security policy
forbids — and the copy collided with a same-named file, so the user got a
link to Project_1.mp3 instead of their own upload, plus an 8.6 MB duplicate.

navi/tools/_internal/areas.py now names the two roots a user owns, and the
four call sites share it. Relative paths still resolve into the sandbox,
and each tool keeps its own way of refusing: terminal returns
sandbox_violation, code_exec silently falls back to the sandbox root. The
share_file refusal lists both roots instead of "outside user sandbox", so
the agent retries in the right one instead of routing around it.

The session directory belongs to the same user: its id arrives from the
runtime context, never from tool arguments, and only the session's owner
can open it.

tools, mcp: a description is a hook, not a manual ...

With 24 tools in a profile the schemas are the largest fixed block of every
request, and they are paid for whether or not the tool is called. Eleven of
them carried a manual's worth of prose in their `description` — examples,
error tables, "common mistakes", the mechanics of the file areas. Reading
them against the manuals first, the manuals already held all of it, and
richer: this was duplication sitting in the one place the model cannot avoid
reading, not knowledge that had nowhere else to live. So the descriptions
became selection hooks — what the tool is for, when to pick it over its
neighbour, and the one rule that cannot wait — and the detail moved to
tool_manual("<tool>"), which costs nothing until the tool is actually in
play.

filesystem, spawn_agent, schedule_recall, manage_recall, scratchpad, plan,
share_file, content_publish, reflect, todo and peer. Descriptions drop from
18.4 KB to 11.5 KB, those tools' schemas from 25.5 KB to 16.8 KB, and a
profile's whole native toolset from 38.3 KB to 29.6 KB (server_admin,
developer; secretary 33.7 → 25.0, navi_code 32.9 → 25.9, tool_developer
37.9 → 29.2, modeler_3d 33.4 → 24.8). Stated as a budget rather than a byte
count: roughly 4k tokens of the model's window per request, back.

Two things were deliberately not shortened. The filesystem edit ladder
(`edit` → `edit_lines` → `smart_edit`, last resort, costs an LLM call) and
todo's mandatory `validation` on `done` both exist to prevent an extra
round trip; a shorter description there would trade tokens for turns. What
todo lost is the prose around the rule, not the rule. `enabled.json` was
left alone too: weather, gmail and get_current_datetime are opt-in and the
DB shows 12, 16 and 40 calls, so they are opt-in tools that are actually
used.

peer had no manual at all, which is how this surfaced: its description was
the only documentation the tool had. manuals/peer.md is now written from
the tool and its /peer route — the ask/status/list actions, the fact that
the hive is only a phone book and the question travels peer-to-peer, the
one-concurrent-answer semaphore, the two independent recursion guards, and
the six error codes.

The MCP server instructions leave the system prompt the same way. They were
8 KB of always-present prose per request, most of it workflow detail the
model only needs when it is about to use that server. Each server now
contributes one line — a new optional `summary` field in mcp_servers.d/*.json,
defaulting to the first sentence of its `instructions` — and
tool_manual("<server>") returns the full text plus the tool names the server
declares. server_admin's MCP block goes from 8.3 KB to 1.3 KB, secretary's
from 8.1 to 1.2. tool_manual learned to answer for a server (a tool name
still wins over a server of the same name, and dash/underscore spelling is
tolerated), and the index names the servers alongside the tools.

One judgement call worth recording: gnexus-book's and navi-web's
instructions end in an absolute "NEVER bypass these tools with filesystem,
terminal or code_exec" rule. Moving that on demand would have been a
behavioural regression dressed as a token saving, so those two `summary`
fields carry the prohibition verbatim alongside the hook, and it stays
always visible.

docs/tools.md gains a section on the split (a description is paid for every
request, a manual only when the tool is used), which is where the next
person will look before trimming a description back into a manual.

Full suite green (1577 passed, 1 skipped). No frontend change and no new
dependency, so the deploy is a pull and a restart.

Pass explicit ToolContext to tools instead of hidden ContextVars ...

Add ToolContext dataclass (session_id, event_sink, stop_event, model,
user_id, user_role, user_info) and thread it through the execution chain:
Agent._execute_tools_with_sink → ToolExecutor → tool.execute().

All ~25 tools updated to accept ctx parameter. Tools that previously
read ContextVar now prefer ctx when provided, falling back to
ContextVar for backward compatibility.

Tests updated to pass ToolContext explicitly — no more test fixtures
that set current_session_id / current_user_id ContextVars.

ContextVar setters remain as fallback for non-tool consumers
(ai_helper, context_builder, planning) and will be removed in a
follow-up refactor.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Fix session file URLs (add /api prefix) and WebGL error handling in STL viewer ...

Backend:
- _file_url in content_store.py now returns /api/sessions/... instead of /sessions/...
- share_file.py URL construction updated to include /api
- content_publish.py docstring updated to reflect correct endpoint

Frontend:
- contentLinks.js: avoid double /api prefix in dev mode when backend already returns it
- stl.html: replace throw err with return after showing WebGL fallback message
- Rebuild dist

Tests:
- Update expected URLs in test_content_store.py and test_share_file.py

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Refactor: move tool helper modules into _internal subpackage ...

Moves non-tool infrastructure out of navi/tools/ root so that only
actual tool classes live there:

  base.py           → _internal/base.py
  loader.py         → _internal/loader.py
  middleware.py     → _internal/middleware.py
  logging_middleware.py → _internal/logging_middleware.py
  _time_parser.py   → _internal/time_parser.py

All imports updated across core/, api/, mcp/, tools/, and tests/.
No proxy files remain in navi/tools/ root.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Add multi-user sandbox: filesystem, terminal, code_exec, security policy ...

- filesystem, share_file: sandbox non-admin users to user_data/<user_id>/
- terminal: working_dir sandbox + allowlist + dangerous pattern block for users
- code_exec: sandbox CWD and temp files to user_data/<user_id>/ for users
- context_builder: inject dynamic security policy into LLM context (user/admin)
- config: terminal_user_allowed_commands setting
- agent: wire user_id/user_role through ContextBuilder.build()
- base: add current_user_role ContextVar; run_ephemeral inherits role

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Add per-user filesystem sandbox via current_user_id ContextVar ...

- tools/base.py: add current_user_id ContextVar (set by Agent before
  every tool call, cleared after)
- core/agent.py: set current_user_id in run_stream from session.user_id
  and in run_ephemeral from parent_session.user_id; restore in finally
- tools/filesystem.py: _check_path resolves all paths inside
  user_data/<user_id>/ when current_user_id is present; legacy mode
  (no user_id) falls back to FS_ALLOWED_PATHS
- tools/share_file.py: validate source path is inside user sandbox

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Clarify share file publishing boundaries

Make server I/O non-blocking; update docs ...

- Wrap all heavy filesystem ops in asyncio.to_thread: filesystem tool
  (read/write/append/list/find/info/move/delete/query/smart_edit),
  image_view (read_bytes), share_file (shutil.copy2), write_tool
  (write_text, _register_user_tool), session_files (shutil.rmtree,
  iterdir), sessions upload endpoint (sync open/write → to_thread)
- Make delete_session_dir async; update its caller in sessions.py
- docs/config.md: fix wrong defaults (threshold 0.70, keep_recent 8),
  remove phantom SESSION_FILES_TTL_HOURS, add LLM timeouts, DATABASE_URL,
  PUBLIC_URL, Gmail, CONTEXT_SUMMARY_MAX_TOKENS sections
- docs/profiles.md: add missing tool_developer profile to table
- android-client: add WebView remote debugging; remove unused toolbar menu
- Remove stale helper scripts and test files

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Improve subagent system: isolated tools, custom prompts, context transfer, timeout ...

AgentProfile:
- New fields: subagent_tools, subagent_planning_enabled, subagent_system_prompt
- loader.py: loads subagent_tools/subagent_planning_enabled from config.json,
  reads optional subagent_system_prompt.txt per profile

Profiles:
- Each profile now has a dedicated subagent_tools list (focused subset, no admin tools)
- subagent_planning_enabled: false (configurable per profile)
- New subagent_system_prompt.txt per profile with executor-focused instructions

run_ephemeral:
- Uses profile.subagent_tools instead of enabled_tools
- Builds subagent context without persona or profiles block (focused executor)
- Injects subagent_system_prompt after profile.system_prompt
- Accepts context_transfer: priming exchange injected before task message
- Wall-clock timeout (default 5 min) checked per iteration
- Returns (result_text, completed: bool) instead of bare string
- Optionally runs planning phase if profile.subagent_planning_enabled

spawn_agent:
- Removed briefing param; task is now fully self-contained
- Added system_prompt param: custom injected prompt for this specific task
- Auto-reads parent scratchpad context_transfer section via get_section()
- Result prefixed with [STATUS: completed|limit_reached]
- Timeout 300s

scratchpad:
- Added get_section(session_id, section) helper for cross-session reads

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Webclient UI improvements + backend fixes ...

Webclient:
- Draft persistence across page refreshes (localStorage, reactive watch)
- Image lightbox modal using UI kit classes on thumbnail click
- Copy button on user and assistant messages
- Selection reply toolbar: select assistant text → quote inserted into input
- User message rendering: proper HTML escaping, styled blockquote for > replies
- Markdown table fix: preprocessor to inject missing separator rows
- Planning status labels (rebuild dist)

Backend:
- Developer profile: enable subagent delegation, increase max_iterations to 35
- share_file: updated description + manual with absolute path requirement and URL sharing
- persona.txt: instructions for quote replies and GFM table format

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Add share_file tool and session-lifetime file storage ...

Session file directories now live until the session is deleted, not
24h TTL. Cleanup loop only removes orphaned dirs (session gone from DB).

New share_file tool: copies any file to the session directory and returns
a clickable download URL. Navi can call this after generating any file
the user will want to keep.

New GET /sessions/{id}/files/{filename} endpoint serves files with
correct Content-Disposition (inline for images/HTML/PDF, attachment
for everything else).

Added PUBLIC_URL config key for building correct download links behind
reverse proxies.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>