依國家、方案類型、關鍵字搜尋一心eSIM的商品清單，一次回傳多筆結果讓使用者自己比較。 適用情境：使用者想瀏覽/比較某國家的多個方案，或已經明確講出要哪種類型 （例如指定「總量型」或「每日定量型」）。 如果使用者是描述旅遊情境（去哪個國家玩幾天、上網習慣如何）要你直接建議選哪個， 改用recommend_esim_plan讓它幫忙評分挑選，不要自己從這個工具的結果裡用猜的。
| Name | Required | Description | Default |
|---|---|---|---|
| limit | No | 最多回傳幾筆，預設20，避免結果過多 | |
| country | No | 國家名稱，英文或中文皆可，模糊比對，例如 Japan、日本、韓國。不確定系統裡的正確名稱時，先呼叫list_esim_countries確認 | |
| keyword | No | 自由關鍵字，比對商品名稱/描述/規格文字 | |
| planType | No | 方案類型，留空代表不限類型 |
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description must disclose safety and side effects. It says it returns multiple results for comparison, but it does not explicitly state that it is read-only, free of side effects, or mention any rate limits or error behavior. The read-only nature is implied by 'search' but not explicitly declared, which is a notable gap given the full burden is on the description.
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 compact: a one-sentence purpose, then a conditional usage guideline, then a clear alternative reference. It is front-loaded with the core function and contains no filler or redundancy. Every sentence contributes value.
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?
With 4 optional parameters and no output schema, the description explains that multiple results are returned and differentiates from the recommendation tool. However, it does not describe the structure of the returned results or point to 'get_esim_plan_detail' for deeper information, which is a minor but relevant gap for a tool without an explicit output schema.
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?
The input schema has 100% description coverage, with detailed parameter descriptions including defaults and cross-tool guidance. The main description only mentions 'country, plan type, keyword' without adding new semantic meaning beyond the schema. The baseline of 3 is appropriate because the schema does the heavy lifting.
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 uses a specific verb 'search' with a clear resource ('eSIM product list') and explicitly lists filtering dimensions (country, plan type, keyword). It also distinguishes itself from 'recommend_esim_plan' by contrasting browsing/comparing vs. getting a scoring-based recommendation, which differentiates it from a key sibling.
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?
Explicitly states when to use (browse/compare multiple plans or when user specifies a plan type) and when not to use (travel scenario where the user needs a direct recommendation), naming the alternative 'recommend_esim_plan'. Also, the country parameter description suggests calling 'list_esim_countries' when uncertain, providing additional guidance.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
Add one secure layer between your agents and this server.
Each tool targets a distinct task: listing countries, searching plans, fetching details, recommending based on needs, and creating orders. The two plan-finding tools are clearly distinguished by their usage intent (browsing vs. recommendation), eliminating ambiguity.
All tool names follow a consistent verb_noun snake_case pattern (list, get, search, recommend, create) with the 'esim_plan' or 'esim_order' object. This uniformity makes the set highly predictable.
With 5 tools, the server is tightly scoped to the eSIM sales journey: discovery, search, detail, recommendation, and order creation. Each tool earns its place without redundancy or bloat.
The server covers the full pre-purchase lifecycle comprehensively, from country listing to order creation with payment links. A minor gap is the lack of an order status or retrieval tool, but this does not hinder the primary workflow of purchasing an eSIM plan.
