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

Annotations already declare destructiveHint=true, idempotentHint=true and openWorldHint=true, so the safety profile is covered. The description adds genuinely non-redundant behavior: partial-patch semantics, position being zero-based, campaign targeting precedence (campaignId over GROWSURF_CAMPAIGN_ID), and that the uploadTicket is one-time and the uploadResult must be unmodified. It stops short of stating what a FILE replacement does to the previously stored asset.

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?

Three tight sentences, front-loaded with the core operation and the FILE caveat before the targeting rule. The API reference URL is the only marginally expendable element; nothing else is filler.

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 12-parameter tool with a nested uploadResult object and intricate if/then schema constraints, the description surfaces the highest-risk rules (one-time ticket, unmodified result, partial update, position base). An output schema exists, so return values need no explanation. Missing only the create-vs-update and prepare-upload hand-off guidance.

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 only 42%, so the description must compensate; it does so for uploadTicket/uploadResult, position and campaignId (resolution rules), but says nothing about type/url/text/category/title/isPublished interactions. The conditional schema (LINK needs url, TEXT needs text, FILE needs the ticket pair) is largely left to the schema to convey.

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?

States a specific verb and resource ('Update at least one participant resource field') plus a second explicit operation (moving it to a zero-based position). The partial-update framing distinguishes it from create_program_resource and delete_program_resource, though those siblings are not named.

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?

Useful context is implied by 'Only supplied fields change' and by the FILE/uploadTicket requirement, but there is no explicit routing guidance (e.g. use prepare_program_resource_file first, use create_program_resource for new resources). It gives conditions but never names an alternative or an exclusion.

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