Report a Gmail message or thread as spam by adding the SPAM label and removing it from INBOX. Use it to handle unwanted mail; the action is reversible and audited with a reason.
Reports a message/thread as spam (adds SPAM, removes INBOX). Reversible via gmail_unmark_spam. Audited with reason.
| Name | Required | Description | Default |
|---|---|---|---|
| id | Yes | ||
| type | No | message | |
| reason | No | user-reported spam |
Changes observed during successful MCP inspections.
v1.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already cover the safety profile (readOnlyHint=false, idempotentHint=true, destructiveHint=false); the description adds genuine value beyond them by disclosing the concrete label side effects, reversibility, and that the action is audited with the supplied reason. It stops short of mentioning required scopes or any limits, so not 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?
Three tight clauses, front-loaded with the action and its effect, then reversibility, then the audit note. Zero filler.
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?
Behavior is well covered for a mutation tool, but with an entirely undescribed parameter set and no output schema, the agent still lacks guidance on what id accepts and what defaults apply. Adequate, with a clear gap.
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?
Schema description coverage is 0%, so the description must carry the parameter burden, and it only partially does: 'message/thread' hints at the type enum and 'Audited with reason' hints at the reason field, but id format, defaults, and the 3-500 char reason constraint go unmentioned. Two of three parameters remain opaque to the agent.
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 ('Reports a message/thread as spam') and even spells out the exact label mutation (adds SPAM, removes INBOX). This clearly separates it from siblings like gmail_trash_message and gmail_unmark_spam without opening any schema.
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?
Names the exact reversal path ('Reversible via gmail_unmark_spam'), which tells the agent when to reach for the sibling instead. It does not, however, contrast with gmail_trash_message or gmail_restore_message, so the choice among destructive-ish actions is left partly to inference.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.