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

Annotations already cover the safety profile (readOnlyHint=true, idempotentHint=true, destructiveHint=false, openWorldHint=true), so the bar is lower. The description adds substantive non-annotation behavior: the exact compliance filter (all four standards at last quarter-end), largest-first ordering, and that index funds are included in the results. It omits any result-count limit or pagination behavior.

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?

Front-loaded with the purpose, followed by the qualification criteria and a short actionable routing sentence. Every clause carries information, though the criteria sentence is dense and packs multiple distinct facts (industry matching, compliance standards, ordering, index funds) into one run-on string.

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?

There is no output schema, so the description carries the burden of describing returns and it does: company universe, compliance condition, ordering, and the inclusion of Shariah index funds. Combined with one fully documented parameter, nothing an agent needs to call this correctly is missing.

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 100% and the single parameter is already documented as 'a US listing symbol or company name.' The description only refers to it obliquely as 'a holding,' so it adds no syntax, accepted-format, or fallback guidance beyond the schema. Baseline 3 is appropriate when the schema does the heavy lifting for one parameter.

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 action and resource: find halal-permitted replacement companies for a given holding, constrained to the same or nearest related industry. It also states the qualification criteria (business permitted, debt passes all four standards at last quarter-end), the ordering (largest first), and the extra content (Shariah index funds for US/UK investors). An agent can distinguish this from mizan_screen_company and mizan_screen_portfolio without opening any 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?

Explicitly frames the tool as replacing an existing holding and adds a workflow instruction: 'Screen a pick live with screen_company before buying.' That is a clear next step, but the description never states when this tool should be preferred over siblings like mizan_screen_portfolio or the halalornot screening tools, so no exclusion guidance is provided.

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