list_subscription_offers

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

With no annotations supplied, the description carries the safety burden and does so minimally but adequately by declaring "Read-only." It says nothing about return shape, pagination, or what happens if the base plan id does not exist, so the behavioral picture is thin for a tool with zero annotation coverage.

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, scope first then the special-case parameter, with the read-only guarantee trailing — no wasted wording. It is perhaps slightly too terse given the lack of annotations, but nothing is redundant.

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 three-parameter, non-nested listing tool with no output schema and full schema coverage, the description covers purpose, the key parameter nuance, and the safety property. Only pagination and failure behavior are absent, which are minor for this complexity level.

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 all three parameters are already documented, including "Base plan id, or '-' for all." The description's restatement of the '-' sentinel adds emphasis but no new syntax or format meaning, so the baseline 3 applies.

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?

"List the offers (free trials, intro prices, upgrades) under a base plan" pairs a specific verb with a specific resource and even enumerates the offer kinds, so the agent knows exactly what comes back. It stops short of naming a sibling such as get_subscription_offer, so differentiation from the single-offer tool is left implicit.

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?

It supplies one concrete usage instruction — pass basePlanId '-' to span all base plans — which is genuinely actionable. However it never says when to prefer this over get_subscription_offer or list_subscriptions, and gives no prerequisites or error conditions, so guidance is implied rather than explicit.

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