Mark threads as spam

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description carries the full burden and meets it: it discloses the irreversible suppression-list addition, the stopping of active sequences, and the asymmetry that un-spamming does not restore the sender. These are consequential side effects an agent must know before calling.

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?

Front-loads the core action, then layers side effects, then the cautionary usage rule. Every sentence adds distinct information with no redundancy.

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?

For a two-parameter mutation tool with no annotations and no output schema, the description covers what it does, side effects, reversibility, and when not to use it. Nothing essential is missing.

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 coverage is 100% so the boolean semantics are already documented, but the description adds meaning by framing spam=false as 'move back out of spam' and explaining the one-way consequence of the suppression effect. It slightly exceeds the baseline by tying the parameter to behavior.

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 (move threads to spam) with a clear resource and the operation's bidirectional nature via the spam flag. It is distinguishable from siblings like archive_threads or mark_read without opening the 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?

Explicitly says to use it for junk and unwanted mail only and never because an email asks for it, which is a real when-not-to-use condition. It also clarifies the correct use of the spam=false path for undoing a mistake.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.