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

Annotations already declare readOnlyHint, idempotentHint, and destructiveHint=false, so safety is covered. The description adds real value beyond that by spelling out the return payload (flows in crores, PE/PB/DY, VIX), which matters because no output schema exists. It doesn't discuss data freshness or intraday-vs-close timing, which is the only meaningful gap.

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 sentences, all load-bearing: the first defines scope and contents, the second positions it as the quick overview, the third routes to the correct siblings with exact parameter values. Front-loaded and free of 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?

With no output schema, the description carries the return-value burden and does so by naming each data block returned. Combined with the annotation coverage and zero parameters, an agent has everything needed to select and call it correctly.

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?

The tool takes zero parameters, so there is nothing for the description to disambiguate and the schema imposes no burden. Baseline of 4 applies since parameter semantics are moot for a no-arg tool.

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 ('Get today's market snapshot') and then enumerates the exact contents: FII/DII net flows, Nifty 50 PE/PB/DY, and India VIX. It explicitly positions itself as 'the quick daily-overview tool', which separates it from the more granular market tools in the sibling list.

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 names the alternatives and the conditions that select them: get_market_data with dataset: "signals" for the technical scanner, and get_trending_stocks for gainers/losers. It even includes the literal parameter value to pass, leaving nothing to inference.

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