Fx Set

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

No annotations are provided, so the description carries the full behavioral burden. '(merge)' does signal non-replacement semantics, which is useful. But there is no mention of permissions, reversibility, error behavior if the index is invalid, or what parts of the effect state are preserved – all important for a mutation tool.

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 single sentence is front-loaded and wastes no words. It is terse to the point of under-specification, but the sentence structure itself is efficient.

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 4-param required mutation tool with no annotations, zero schema description coverage, and nested objects, this description is far too thin. The presence of an output schema means return values need not be explained, but parameter meaning and usage context are missing.

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% and the description mentions none of the four parameters by name (project, target, index, params). 'effect #index on target' only loosely gestures at index and target, leaving project and params entirely unexplained at zero schema coverage. This is a severe 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?

States a verb (Update) and a resource (params of effect #index on target), but 'fx' and 'index' are cryptic without domain context and no sibling is named to differentiate (fx_add vs fx_remove vs fx_set). The 'effect #index on target' phrasing implies a hierarchy but doesn't explain it.

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?

No guidance on when to use this versus fx_add or fx_help. The '(merge)' hint implies it updates a subset of params, but no explicit conditions, prerequisites, or alternatives are stated.

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