Set expression

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

Annotations already declare destructiveHint=true, idempotentHint=true and readOnlyHint=false, so the safety profile is covered; the description adds the return payload (expression, enabled flag, AE error, evaluated value at current time), which matters since there is no output schema. It does not state that an existing expression is overwritten irreversibly or point at ae_undo, which is the main remaining behavioral gap for a destructive write.

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?

Two sentences, front-loaded with the action and the clear-case before the sibling routing list. The dense parenthetical of four tool names is information-dense rather than wasteful, and no sentence is filler.

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 no-output-schema mutation tool, the description supplies the return fields, the clearing convention and alternatives, which is nearly everything an agent needs. It stops short of noting irreversibility of overwrite or the recovery path via ae_undo, a minor gap given destructiveHint=true.

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 100%, including the enabled flag and the 'empty string removes the expression' semantics, so the schema carries the parameter burden. The description only restates the empty-string clearing convention and adds the 'one property' scoping; it contributes nothing about path/layer/comp resolution 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 set (set, replace, clear) applied to a specific resource (an expression on one property), and the parenthetical '(empty string)' defines the clear case immediately. It explicitly distinguishes itself from ae_check_expression, ae_replace_in_expressions and ae_get_expressions, so an agent can differentiate without opening other 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?

The second sentence gives explicit routing rules: use ae_check_expression to try without keeping, ae_replace_in_expressions for bulk text edits, ae_get_expressions to list. Each alternative comes with the condition that selects it, and it notes all are reached via ae_call.

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