GTM: Versions

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safety profile is covered; the description adds genuinely new behavior beyond that — newest-first sort order, the per-version metrics returned, and a live=true flag for the published version. It omits how the limit/pagination behaves in practice and whether deleted versions are hidden by default, which keeps it out of 5 territory.

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?

Two tight sentences: the first states what is returned and how it is ordered, the second gives the downstream workflow. No filler, no restating of the title, and the most useful information leads.

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?

With no output schema, the description usefully describes the shape of each returned entry and the live marker, which is exactly what an agent needs. It is only slightly incomplete on paging limits and default handling of deleted versions, which affects how the required accountId/containerId are used.

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 only 50%: accountId and containerId are undocumented in both schema and description, and the description says nothing about limit or includeDeleted. The only parameter-like reference is containerVersionId, which belongs to a sibling tool, so the description does not compensate for the coverage gap.

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?

Names a specific verb and resource (lists container versions) and immediately discloses the ordering and the fields each entry carries (name, tag/trigger/variable counts, live=true). It also distinguishes itself from gtm_export_container and gtm_publish_version by describing the workflow that uses them, so an agent can separate these 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?

Gives a concrete use case — this is the entry point for a rollback — and routes the agent to gtm_export_container(containerVersionId) for inspection and gtm_publish_version for the write. It stops short of explicit when-not-to-use guidance (e.g. use gtm_lookup_container or gtm_export_version for a single version's contents), but the intended context is clear.

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