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

Annotations already declare destructiveHint=true and readOnlyHint=false, so the description's mutation warning is consistent. The description adds valuable context beyond annotations: it explains the partial effect (already-sent messages unaffected, contacts remain), and it discloses the shared-workspace side effect (no per-caller isolation, visible/editable by others). This is meaningful behavioral context that annotations alone do not provide.

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 is compact and front-loaded: the core action and effect appear in the first sentence, followed by the use-case signal and the shared-workspace caveat. Every sentence earns its place, and there is no redundant restatement of the tool name or title.

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 mutation tool with an output schema and clear annotations, the description covers the essential behavioral aspects: what happens, what doesn't happen, when to use it, and the shared-workspace side effect. It does not describe the output/return value, but the presence of an output schema reduces the need for that. It also doesn't mention idempotency, but annotations already cover that (idempotentHint=false).

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% and the only parameter (sequence_id) is documented as 'Sequence ID.' The description does not add further parameter-level detail, but with a single required parameter and full schema coverage, the baseline of 3 is appropriate. The description's behavioral context indirectly clarifies that sequence_id refers to the sequence to deactivate, but no additional syntax or format is needed.

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 clearly states the action ('Deactivate a sequence so it stops sending'), the resource (a sequence), and the effect (halts future steps while preserving contacts and already-sent messages). It distinguishes this from sibling tools like archive or remove contacts by explicitly noting what it does not affect.

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 explicitly frames this as 'the stop switch when something is going wrong,' giving a clear when-to-use signal. It also contrasts with sibling tools like post_apollo_emailer_campaigns_remove_or_stop_contact_ids by clarifying that contacts stay in the sequence, which helps an agent choose between aborting the whole sequence vs removing specific contacts.

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