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

No annotations are present, so the description carries the full behavioral burden. It discloses that the tool is deprecated and is one-way only, which is meaningful behavioral context. However, it does not mention what the actual response body returns, output limits, error conditions, or whether it retrieves real-time data, which would help an agent understand the behavior of a read-only search API.

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 sentences long, with the deprecated warning and canonical replacement front-loaded to prevent a mistake. The one-sentence functional description that follows is efficient and contains no fluff. Every sentence 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?

The tool has only 3 input parameters, all are required, all are fully described in the schema, and the description clarifies the tool's scope and deprecation status. There is no output schema, but the description is sufficient for the agent to know what kind of list it will get. It could stir in more detail about the return structure, but for a deprecated tool that is simply sent to v2, the key selection information is already present.

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?

All three parameters are already explained in the schema with human-readable examples (e.g., 'date' described with YYYY-MM-DD and example). The description adds no additional parameter-level semantics beyond telling the agent that it searches from one port to another on a specific date. Since schema coverage is 100%, this is the appropriate baseline.

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 opens with a clear violation: 'Get a list of available one-way ferry trips between two ports on a specific date.' It names the exact resource (ferry trips), the action (search/list), and the scope (one-way, two ports, date), which distinguishes it from other ferryhopper tools. The deprecation line further identifies the successor by name, so there is no ambiguity.

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 explicitly says 'Deprecated: prefer search_trips_v2' and explains what the new tool covers that the current tool does not (round-trip search and per-segment availability flags). This is a clear, direct when-to-use alternative for agents, and the advantage is more evidence about the new tool, so the agent can decide which to call.

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