set an agent's initial agents.md at create

swarmctl/src/agent.rs

@@ -41,6 +41,9 @@ struct CreateAgentRequest<'a> {
     /// endpoint and not defaulted anywhere, because it is only knowable
     /// from the operator making the choice.
     hive: &'a str,
+    /// The text the agent's `AGENTS.md` starts with; left out when not given.
+    #[serde(skip_serializing_if = "Option::is_none")]
+    agents_md: Option<&'a str>,
 }
 
 /// Run `swarmctl agent create`.
@@ -50,19 +53,30 @@ struct CreateAgentRequest<'a> {
 /// built here keeps that cost inside the one arm that incurs it, the same
 /// way `PathArgs::resolve` is called only in the arms that need the
 /// deployment's env vars.
-pub(crate) fn create(target: &Target, name: &str, hive: &str) -> Result<()> {
+pub(crate) fn create(
+    target: &Target,
+    name: &str,
+    hive: &str,
+    agents_md: Option<&Path>,
+) -> Result<()> {
     // Client-side before the round trip, so a typo is an immediate local
     // error rather than a 400 the operator has to wait for. The controller
     // validates both again — that is the gate that matters, this is the
     // one that is fast.
     let name = parse_ident(name, "agent name")?;
     let hive = parse_ident(hive, "hive")?;
+    let agents_md = agents_md
+        .map(|path| {
+            std::fs::read_to_string(path)
+                .with_context(|| format!("reading --agents-md {}", path.display()))
+        })
+        .transpose()?;
 
     let rt = tokio::runtime::Builder::new_current_thread()
         .enable_all()
         .build()
         .context("starting a tokio runtime for the controller request")?;
-    let resp = rt.block_on(post_create(target, &name, &hive))?;
+    let resp = rt.block_on(post_create(target, &name, &hive, agents_md.as_deref()))?;
 
     println!("queued: job node {}", resp.node_id);
     println!(
@@ -114,11 +128,20 @@ pub(crate) fn mint_forge_token(target: &Target, name: &str) -> Result<()> {
 }
 
 /// One `POST /api/agents` round trip at the controller.
-async fn post_create(target: &Target, name: &str, hive: &str) -> Result<CreateAgentResponse> {
+async fn post_create(
+    target: &Target,
+    name: &str,
+    hive: &str,
+    agents_md: Option<&str>,
+) -> Result<CreateAgentResponse> {
     post(
         target,
         "/api/agents",
-        &CreateAgentRequest { name, hive },
+        &CreateAgentRequest {
+            name,
+            hive,
+            agents_md,
+        },
         "create-agent",
     )
     .await