neoclide/coc.nvim · error · Error

SemanticTokens provider not found for ${this.doc.uri}

Error message

SemanticTokens provider not found for ${this.doc.uri}

What it means

checkState throws this when the semantic tokens configuration is enabled for the filetype, but the buffer either has no attached server that registers a SemanticTokens provider (hasProvider false) or the server did not register the token legend needed to decode token types (hasLegend false).

Source

Thrown at src/handler/semanticTokens/buffer.ts:219

  private get buffer(): Buffer {
    return this.nvim.createBuffer(this.bufnr)
  }

  public get enabled(): boolean {
    if (!this.configEnabled || !this.hasLegend) return false
    return this.hasProvider
  }

  private get shouldHighlight(): boolean {
    if (!this.enabled) return false
    const { doc } = this
    if (doc.dirty || doc.version === this._version) return false
    return true
  }

  public checkState(): void {
    if (!this.configEnabled) throw new Error(`Semantic tokens highlight not enabled for current filetype: ${this.doc.filetype}`)
    if (!this.hasProvider || !this.hasLegend) throw new Error(`SemanticTokens provider not found for ${this.doc.uri}`)
  }

  public async getTokenRanges(
    tokens: number[],
    legend: SemanticTokensLegend,
    token: CancellationToken): Promise<SemanticTokenRange[] | null> {
    let currentLine = 0
    let currentCharacter = 0
    let highlights: SemanticTokenRange[] = []
    let toBytes: (characterIndex: number) => number | undefined
    let textDocument = this.doc.textDocument
    let tickStart = Date.now()
    for (let i = 0; i < tokens.length; i += 5) {
      if (i == 0 || Date.now() - tickStart > yieldEveryMilliseconds) {
        await waitImmediate()
        if (token.isCancellationRequested) break
        tickStart = Date.now()
      }

View on GitHub (pinned to 50e974d969)

Solutions

1. Upgrade the language server to one supporting semanticTokens with a proper legend.
2. Verify capability with `:CocCommand document.checkBuffer` and check `:CocInfo` for client attachment.
3. Run `:CocRestart` if the server exited and the buffer is orphaned.
4. Remove the filetype from `semanticTokens.filetypes` if the server will never support it, to silence refresh attempts.

// only refresh when a semanticTokens provider is attached for this uri
const caps = await coc.commands.executeCommand('document.checkBuffer')
if (!caps?.capabilities?.semanticTokensProvider) return

try {
  await buffer.checkState()
} catch (e) {
  if (String(e?.message).includes('SemanticTokens provider not found')) return
  throw e
}

When it happens

Trigger: Semantic highlight enabled for the filetype, then a refresh runs on a buffer where `languages.hasProvider(SemanticTokens, uri)` is false or `languages.getLegend(...)` returned undefined — no server attached, server without semanticTokens capability, or server registered the capability without a legend.

Common situations: Language server version without semanticTokens support (pre-LSP 3.16); capability registered but legend negotiation failed; buffer detached from its client (server exited) while highlights refresh.

Related errors

• Inlay hint provider not found for current document
• Rename provider not found for current buffer
• Semantic tokens highlight not enabled for current filetype:
• Unable to perform semantic highlights for current buffer.
• Filetype "${this.doc.filetype}" not enabled by inlayHint con

AI-assisted analysis of neoclide/coc.nvim@50e974d969 (2026-08-31). Data as JSON: /api/errors/1e0a213adb332e1d. Report an issue: GitHub.