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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive), so the bar is lower. The description's contribution is the 'Today's' recency signal plus the enumeration of returned stat families, which is genuinely useful because no output schema exists. It still says nothing about slate scope, refresh cadence, or whether stats are per-game or per-slate.

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?

A single dense sentence that front-loads the source and recency before listing fields; nothing is wasted. It is a bit list-heavy, but for a data-feed tool that list is the payload description and 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?

With no output schema, the description partially compensates by enumerating returned fields, which is the most valuable part. It remains incomplete on the points an agent needs to call it correctly: which slate/day the projections cover, how team/position filters behave, and how the result relates to sibling projection sets.

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 75%, just under the high-coverage baseline, and the schema itself documents team, limit, and position. The description implicitly maps its stat list to the sort_by enum values (proj_own, proj_hr, proj_k) but never explains the team or position filters or the interaction between the row limit and the plan limit noted in the schema.

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 identifies the resource ('Today's BankrollSZN MLB DFS projections') and enumerates the stat categories returned, so an agent knows roughly what comes back. However it is a noun phrase with no verb, and nothing distinguishes it from closely related siblings such as invoke_mlb_player_pool, invoke_mlb_ownership_by_contest, or invoke_mlb_props, several of which overlap the listed fields (ownership, HR, K).

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?

There is no statement of when to use this tool versus the many alternative MLB endpoints in the sibling list. The only implied usage is that it is a DFS projections feed; nothing tells the agent whether to reach for this instead of invoke_mlb_player_pool or invoke_mlb_ownership_by_contest, or what prerequisites (e.g., a slate) apply.

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