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

Annotations already declare readOnly, idempotent, non-destructive, closed-world behavior, so the safety profile is covered externally. The description adds useful search semantics (which fields are matched, that results include per-story links) but says nothing about ranking, result truncation, or empty-result behavior beyond what the schema's limit already conveys.

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, front-loaded with purpose followed by match/return behavior, with no filler. Every clause 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?

All-optional search tool with four fully documented params and no output schema; the description partially covers the return shape ('link to each story page'). Missing only secondary details like result ordering or behavior when no matches are found.

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% — every parameter (cause, limit, query, location) has its own documented semantics including examples and the list_causes cross-reference. The description adds no parameter-level detail, so the baseline 3 is appropriate.

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 ('Search real charity stories a brand could fund as a cause-marketing campaign') and clarifies the match surface (titles, summaries, charities, causes, places) plus what comes back (best matches with a story-page link). This cleanly separates it from get_campaign_story (single fetch) and list_causes (enumeration of cause values).

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?

Gives clear context for when to reach for it — discovering fundable stories for a cause-marketing campaign — which implies the search-first workflow. It does not name alternatives or exclusions (e.g., 'use get_campaign_story for a story you already have an ID for'), so it falls just short of full routing guidance.

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