pi: generate mcp.json from ~/.config/pi/mcp.d fragments

pi reads user-level MCP servers from one file, and a private layer
linked that file to the same copy on every host -- so every host got a
server only one machine could run. Build it the way models.json is
built, from fragments another layer or one machine drops in mcp.d; this
repo ships none, and with none the file is left absent.

pi-models.py becomes pi-merge.py, which takes the key to merge and an
optional base file, and serves both.

1 files changed, 28 insertions, 2 deletions

diff --git a/link/pi.sh b/link/pi.sh
index 5aec48f..727ed2f 100755
--- a/link/pi.sh
+++ b/link/pi.sh
@@ -1,6 +1,7 @@
 #!/bin/bash
 
-# pi's extensions directory, and its settings.json and models.json, generated.
+# pi's extensions directory, and its settings.json, models.json and mcp.json,
+# generated.
 # Dry run by default; pass `yes` to apply.
 
 set -euo pipefail
@@ -98,7 +99,8 @@ esac
 # never writes it, keeping its runtime state in the sibling models-store.json --
 # so what lands is whatever the repo and the fragments say. A hand-edit of
 # ~/.pi/agent/models.json does not survive a relink; put it in a fragment.
-pi_models_out="$(DRY_RUN="$is_dry_run" python3 "$dotfiles_dir/link/pi-models.py" \
+pi_models_out="$(DRY_RUN="$is_dry_run" python3 "$dotfiles_dir/link/pi-merge.py" \
+  providers \
   "$config_dir/pi/models.json" \
   "$xdg_config_dir/pi/models.d" \
   "$pi_dir/models.json")"
@@ -113,3 +115,27 @@ do
     error)       red "pi models: ${line#*:}" ;;
   esac
 done <<< "$pi_models_out"
+
+# pi's mcp.json, the same way: pi reads user-level MCP servers from this one
+# file only, and the servers are another layer's or one machine's business --
+# a browser on one host, a server behind a credential -- so this repo ships
+# none. It is built from every ~/.config/pi/mcp.d/*.json alone, and left
+# absent where there are none. It used to be a private layer's link to one
+# file for every host, which gave each of them a server only one could run.
+# `pi mcp add` writes here and does not survive a relink; add a fragment.
+pi_mcp_out="$(DRY_RUN="$is_dry_run" python3 "$dotfiles_dir/link/pi-merge.py" \
+  mcpServers \
+  - \
+  "$xdg_config_dir/pi/mcp.d" \
+  "$pi_dir/mcp.json")"
+
+while IFS= read -r line
+do
+  case "${line%%:*}" in
+    note)        yellow "pi mcp: ${line#*:}" ;;
+    wrote)       green "pi mcp: ${line#*:}" ;;
+    unchanged)   green "pi mcp: unchanged" ;;
+    would-write) yellow "pi mcp will be generated: ${line#*:}" ;;
+    error)       red "pi mcp: ${line#*:}" ;;
+  esac
+done <<< "$pi_mcp_out"