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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false. The description adds real behavioral context beyond that: the audit_status=PASS usability filter and the internal structure of each template (greeting text plus suggested question → answer pairs). No contradictions; only minor gaps like pagination are unstated.

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 tightly packed sentences, front-loaded with the core verb+resource, then scope, then the sibling pointer. Every clause carries distinct information; no redundancy or 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?

Output schema exists, so return values need not be explained. The description covers purpose, gating constraint, template structure, and the creation sibling. The only residue is the undocumented advertiser_id parameter, which is minor for a single-param read tool.

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 single parameter advertiser_id has 0% schema description coverage and is never mentioned in the description. The phrase 'on the account' implies an advertiser/account scope but does not define the parameter's meaning or format. With only one param, this is a mild gap, so baseline 3.

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 (Lists) and resource (TikTok WELCOME-CHAT / automated message templates), and situates it in the domain by noting the auto_message_id is required on every DM/messaging ad. It also names the sibling create_tiktok_auto_message, so an agent can distinguish it from adjacent tools without opening a 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?

Explains the context (needed to obtain the auto_message_id for messaging ads) and routes creation to create_tiktok_auto_message. Explicitly states the audit_status=PASS gating constraint for usability. It lacks an explicit when-not-to-use statement, but the alternative is clearly identified.

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