pvsyst_update_variant_components

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

With no annotations, the description still discloses key mutation behavior: it replaces existing references only, performs a backup, and enforces a SHA guard. It does not cover permissions, atomicity, or return behavior, but the core safety semantics are unusually well surfaced.

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 two short, front-loaded sentences with no wasted text. The scope and prerequisite are stated before the type caveat, which is appropriate for an agent scanning the definition.

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 mutation tool with no annotations, no output schema, and zero schema description coverage, the description covers the critical SHA prerequisite and backup behavior. However, it is not complete enough about the nested updates payload or the project/variant parameters, leaving meaningful invocation gaps.

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%, so the description must carry parameter meaning. It explains expected_sha256's source and the strict integer requirement for subarray_id, but it leaves project, variant, and especially the nested updates object unexplained.

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 states a specific verb and resource: replace existing PAN/OND/BTR/GEN component references in a variant. The word 'only' clarifies that it does not update other variant parameters, and it names the sibling used to obtain the required SHA value.

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?

It explicitly directs the agent to call pvsyst_get_variant_components first to obtain expected_sha256, which is a clear prerequisite. It also implies that this tool is only for component references rather than general variant parameters, though it does not spell out when not to use it.

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