jdx/mise · error

remote cache action keys must use blake3

Error message

remote cache action keys must use blake3

What it means

RemoteCacheClient::action_result_endpoint refuses to build an action-result URL unless the action's CacheDigest uses the blake3 algorithm. The remote action-result API is keyed exclusively by blake3 digests; any other algorithm (e.g. sha256) is rejected before a request is made. This is a deliberate protocol restriction, not a network failure.

Solutions

1. Ensure the action digest is computed with blake3 (algorithm == "blake3") before calling get_action_result/put_action_result
2. If the digest came from another tool, recompute the action key with blake3 rather than reusing a foreign digest
3. Verify the algorithm string is exactly lowercase "blake3" (no "sha256", no case variants)

Example fix

// before
let action = CacheDigest { algorithm: "sha256".into(), hash, size };
client.get_action_result(&action).await?;
// after
let action = CacheDigest { algorithm: "blake3".into(), hash, size };
client.get_action_result(&action).await?;

fn ensure_blake3_action(digest: &CacheDigest) -> Result<()> {
    digest.validate()?;
    if digest.algorithm != "blake3" {
        bail!("action key must use blake3, got {}", digest.algorithm);
    }
    Ok(())
}

fn is_blake3_action(d: &CacheDigest) -> bool { d.algorithm == "blake3" }

When it happens

Trigger: Calling get_action_result or put_action_result with a CacheDigest whose algorithm field is anything other than "blake3" (e.g. a sha256 digest produced elsewhere, or a hand-constructed digest with a typo like "Blake3").

Common situations: Mixing digests from another CAS or build system that defaults to sha256; constructing CacheDigest values by hand instead of via the library's hashing helpers; case-sensitivity mistakes in the algorithm string.

Understand the failure class

Background: "Must be a positive integer", "Invalid value", "Unsupported": the invalid-argument-value error family, when a library rejects the value you pass — this error's family across 35 libraries.

Related errors

• invalid remote task cache key
• remote action manifest keys must use blake3
• remote cache directory contains duplicate names
• a repository preview directory requires a dry run
• action prediction payload is too large

AI-assisted analysis of jdx/mise@533346cc37 (2026-09-17). Data as JSON: /api/errors/4ecf2bea3d92b8cd. Report an issue: GitHub.

Appendix: source

Thrown at crates/mise-cache-core/src/lib.rs:422

            .redirect(reqwest::redirect::Policy::none())
            .build()?;
        let credential = remote_credential(&config, client.clone())?;
        Ok(Self {
            base_url: normalized_base_url(config.base_url),
            namespace: config.namespace,
            client,
            credential,
            download_timeout: config.download_timeout,
            retries: config.retries,
            capabilities: tokio::sync::OnceCell::new(),
            blob_packs_disabled: AtomicBool::new(false),
        })
    }

    fn action_result_endpoint(&self, action: &CacheDigest) -> Result<Url> {
        action.validate()?;
        if action.algorithm != "blake3" {
            bail!("remote cache action keys must use blake3");
        }
        Ok(self.base_url.join(&format!(
            "v{PROTOCOL_VERSION}/action-results/{}/{}/{}",
            action.algorithm, action.hash, action.size
        ))?)
    }

    fn blob_endpoint(&self, digest: &CacheDigest) -> Result<Url> {
        digest.validate()?;
        Ok(self.base_url.join(&format!(
            "v{PROTOCOL_VERSION}/blobs/{}/{}/{}",
            digest.algorithm, digest.hash, digest.size
        ))?)
    }

    fn capabilities_endpoint(&self) -> Result<Url> {
        Ok(self
            .base_url

View on GitHub (pinned to 533346cc37)