list_accountsLists connected mail accounts with alias, email, protocol, sign-in status, and permissions. Use it to confirm which accounts exist or which alias the user means before acting.
List the connected mail accounts (alias, email, Gmail or IMAP, signed-in status, default, permission mode, calendar access). Call this when unsure which accounts exist or what alias the user means.
| Name | Required | Description | Default |
|---|---|---|---|
No arguments | |||
Changes observed during successful MCP inspections.
v0.3.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true, destructiveHint=false, and openWorldHint=true, so safety and network scope are covered. The description earns credit by disclosing the returned attribute set, which matters because no output schema exists. It does not mention auth prerequisites or cost/latency, which keeps it from a 5.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
Two sentences, zero waste. The returned-field inventory comes first and the usage trigger second, which front-loads the information an agent needs to decide whether calling is worthwhile.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
With no output schema, the description carries the burden of explaining return values and does so thoroughly. Combined with annotations covering safety and a zero-parameter schema, an agent has everything needed to call this correctly without further inspection.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
The tool takes zero parameters and the schema is an empty object at 100% coverage, so there is nothing for the description to disambiguate. Baseline 4 applies; no parameter guidance is needed or missing.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb and resource ('List the connected mail accounts') and enumerates exactly what each entry contains (alias, email, provider type, signed-in status, default flag, permission mode, calendar access). This clearly distinguishes it from siblings like search_emails, list_labels, or authenticate, which operate on mail content or session state rather than the account roster.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
Explicitly gives the triggering condition: 'Call this when unsure which accounts exist or what alias the user means.' That is a real routing rule an agent can act on. It stops short of naming an alternative tool or stating when not to call it (e.g., after an account is already known), so it is clear context without full exclusions.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.