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

No annotations are provided, so the description carries the full behavioral disclosure burden. It helpfully scopes out ratios, bonus sizes, expiry dates, and worth, preventing misinvocation for valuation tasks. It does not state that this is a read-only lookup, does not mention auth requirements, rate limits, pagination behavior, or return format beyond calling itself a route graph.

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 purpose is front-loaded in the first sentence, which is good. The second and third sentences overlap heavily, both listing transfer ratios and bonus sizes as out of scope, and the third sentence's 'Card facts only' framing is redundant and potentially misleading for a transfer-routes tool. It is not egregiously long, but the repetition fails the every-sentence-earns-its-place test.

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?

There is no output schema and no annotations, so the description should do more to explain what a route entry looks like or how results are bounded. It does establish that the output is the route graph only and excludes ratios, bonus sizes, and expiry dates, which is useful. However, it omits pagination behavior, limit handling, and any sense of return shape for a five-parameter query 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 description coverage is 100%, so each of the five parameters is already documented in the input schema. The description adds thematic context—bonus running, destination reachability, route graph scope—but no syntax or format details beyond what the schema supplies. Baseline 3 is appropriate when 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 states the specific resource: loyalty programs a currency transfers to, or currencies reaching a destination, plus whether a transfer bonus is running. It distinguishes its scope from valuation/card-detail siblings by saying it is the route graph only and does not carry ratios or which route is worth taking. However, the closing phrase 'Card facts only' is confusing and weakens the otherwise clear resource statement.

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 implies usage by listing what the tool does not provide (transfer ratios, bonus sizes, expiry, worth), which helps an agent avoid using it for valuation. It does not explicitly name alternatives like estimate_point_value or compare_card_facts, nor does it state when to choose this tool over them. The schema note about calling with neither argument to list every source is useful but sits outside the description.

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