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

The annotation includes idempotentHint: true, and the description adds valuable context beyond that: only provided fields are modified, and money/area units are specified. While it doesn't disclose error behavior or auth requirements, the added partial-update semantics and units are meaningful given the annotation presence.

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 concise sentences, front-loaded with the main purpose and followed by a necessary unit clarification. There is no fluff or redundancy, and every part earns its place.

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?

Given the tool's high complexity (20 parameters, no output schema, sparse annotations), the description is far too brief to be complete. It fails to explain domain-specific fields (e.g., tva_regime, rental_type), value constraints, or any dependencies between parameters, leaving significant gaps for an AI agent.

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 compensate for documenting 20 parameters. The description only provides global unit guidance (euros, m²) and does not explain any specific parameter meanings, types, or constraints, leaving most parameters ambiguous.

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 clearly states the tool updates an existing property ('Met à jour les champs d'un bien immobilier existant'), distinguishing it from other update tools (expense, income, etc.). The added note that only provided fields are modified ('Seuls les champs fournis sont modifiés') further clarifies the specific behavior.

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 description specifies the tool is for existing properties and performs partial updates, which gives clear context for when to use it (vs. creating a property). However, it does not explicitly name alternatives or state when not to use it, so it stops short of full usage guidance.

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