change_effect

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

Annotations already declare the mutation profile (readOnlyHint=false, destructiveHint=false, idempotentHint=false), so the description's added value is the side effect disclosure: existing parameters are wiped and reset to the new model's defaults. That is exactly the non-obvious consequence an agent needs before overwriting a slot. It does not cover failure behavior for invalid type/model strings, which keeps it at 4.

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?

A single front-loaded sentence with no filler, and the destructive side effect is placed inline where it will be read. It is efficient but arguably under-sized for a swap operation with a nested override object.

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 output schema, the description covers the core behavior and the reset side effect but omits what `params` is for, what happens when type/model resolution fails, and whether the slot must already be occupied. Those are meaningful gaps for a 4-parameter nested-schema tool.

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 75% and the schema itself documents the slot index, the enumerated type names, and model substring matching, so baseline is 3. The description adds the 'params reset to defaults' semantics, but it never mentions the optional nested `params` object at all, leaving its override purpose undocumented in both places.

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?

Specific verb+resource: 'Replace the effect in a slot with another type/model'. It is distinguishable from edit_effect (parameter tweaks), add_effect, and remove_effect by virtue of the swap semantics. It stops short of naming those siblings explicitly, which keeps it from a 5.

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?

Usage is only implied: the parenthetical about parameters resetting signals this is the tool for changing an effect's type, as opposed to edit_effect for parameter changes. There is no explicit when-to-use/when-not statement and no alternative named, so the agent must infer the routing from sibling names.

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