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

Annotations already flag destructiveHint=true and idempotentHint=true, so the description only needed to add context; instead the second sentence describes the semantics of linking ("Linking never copies social automation authority..."), which is the opposite operation and muddies rather than clarifies. It never states what removal actually does to the film, whether the unlinking is reversible, or how request_key provides idempotency, which matters for a destructive mutation.

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?

It is only two sentences and not bloated, but the front-loaded clause is vague and the second sentence is off-topic for an unlink tool, so the space is spent inefficiently rather than wasted on length.

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?

An output schema covers return values, but for a destructive, revision-guarded mutation the description still lacks the essential facts: that this removes a film from a series, whether it is reversible, and what request_key is for. It also fails to distinguish itself from link_series_film, which an agent must do correctly or it will make the wrong change.

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 description coverage is 0% across four required parameters, so the description carries the full burden. It hints at expected_revision ("current series revision") and the film, but never explains series_id, film_id, or the purpose of request_key, leaving the most consequential parameter undocumented.

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?

"Change a Series membership" is a vague verb+resource pairing that never says unlink, remove, or detach, so it reads identically to what the sibling link_series_film would do. The only specificity comes from naming the Series revision and Film, which at least identifies the objects involved.

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?

There is no indication of when to use this tool versus link_series_film, which is the single most important routing decision for this name. It also omits prerequisites such as needing a current revision or a separately authorized film as preconditions for invoking.

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