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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world); the description adds ordering ('newest first'), the exact payload shape, and the scoping rule 'only this workspace's: templates are never shared', which explains why openWorldHint is false. It also disambiguates the source film field, useful context beyond structured fields.

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 sentences, tightly front-loaded: the '[read]' tag and resource/ordering lead, then the definition, then the usage rule. The definitional clause 'to make the next one the same way' is slightly embellishment, but the rest is high-signal.

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 responsibly enumerates the returned fields, and annotations already cover safety, so an agent has what it needs to call this. The remaining gap is whether results are paginated or capped for large workspaces and what an empty result looks like.

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 workspace_id parameter is fully documented in the schema (100% coverage) with its default behavior, so the schema carries the load. The description's 'Only this workspace's' reinforces the scoping semantics but adds no format or override guidance beyond the schema.

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+resource ('The workspace's own templates'), its ordering ('newest first'), and the fields returned (ref, name, line, plan's latest version, source film). It also defines the domain concept ('A template is a plan the person saved from one of their films'), which disambiguates it from list_projects and list_media without the agent needing to open schemas.

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?

Explicit trigger ('Use it when the person names one of their templates') plus a named follow-up action pairing with a sibling ('open_plan with its ref makes a new film from it'). It does not state when-not to use it or contrast with list_projects/list_assets, which keeps it short of a 5.

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