film_reading_plan

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

Annotations already cover the safety profile (readOnlyHint, openWorldHint=false), and the description goes further by disclosing the plan's operating constraints: a request budget split into sessions, no parallel sessions, and a mandatory pause of at least an hour after HTTP 429, plus the thumbnail-vs-full-frame policy. These are concrete execution behaviours not present in the annotations. The rate-limit caveat describes guidance embedded in the plan output rather than the tool's own runtime behaviour, which slightly blurs the picture.

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 opening clause before the list of plan contents, and every element (order, thumbnails, budget, rate limit, logging) corresponds to something the agent must act on. It is dense and heavily parenthesised, bordering on a run-on, but there is little that could be cut without losing operational information.

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?

Because an output schema exists, the description is not obliged to enumerate return fields, and annotations cover the read-only nature. The description supplies the execution policy and logging target needed to use the plan correctly. The remaining gaps are the lang parameter and the absence of explicit routing away from the indexed-search siblings.

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 coverage is 50%, so the description needs to compensate for the undocumented half. It touches parish, years, parts, and reading order conceptually, which overlaps with the schema text but adds no format or syntax detail beyond it, and it says nothing about lang. Baseline 3 is appropriate given partial schema coverage and no real semantic addition.

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 a concrete resource and scope: a reading plan for unindexed FamilySearch films, per parish, years, and parts, with an explicit ordering and thumbnail strategy. The word 'unindexed' implicitly contrasts with the indexed-search siblings (search_online, find_sources), but no sibling is named as an alternative the way a 5 would require. An agent can still tell what it produces without opening the schema.

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?

Usage context is implied by 'unindexed' (you use this when records aren't searchable) and by the downstream reference to project_coverage for logging what gets read. However, there is no explicit statement of when-not to use it, nor a named alternative such as plan_research or search_online. Guidance is inferable but not spelled out.

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