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

The description goes well beyond the annotations by disclosing that every existing contact starts receiving emails via connected mailboxes, that writes land in a shared workspace, that there is no per-caller isolation, and that activation affects all workspace users. This materially informs an agent about side effects and shared-state consequences.

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?

The description front-loads the core action and effect, then adds concise, high-value warnings and prerequisite checks. Every sentence contributes useful operational context without padding.

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 single-parameter tool with annotations and an output schema, the description covers what the tool does, side effects, shared-workspace implications, and recommended pre-checks. Nothing essential is missing for an agent to invoke it knowingly.

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% with a clear 'Sequence ID.' description for sequence_id. The tool description adds no deeper meaning about the parameter beyond the schema, which is acceptable but not extra value.

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?

The description states a specific action ('Activate a sequence') and its immediate consequence ('makes it start sending'). It clearly identifies the resource being acted on and distinguishes the tool from siblings like abort and archive by focusing on activation.

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?

The description provides clear context and prerequisites: the agent should check membership with post_apollo_emailer_campaigns_search and mailbox health with get_apollo_email_accounts before activating. However, it does not explicitly name alternatives or state when not to use this tool, so it stops short of full when/when-not guidance.

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