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. The description adds genuine value beyond them by disclosing data freshness — quotes are end-of-session, not live streaming — which prevents an agent from mistaking this for a real-time feed.

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 sentence with the core capability front-loaded and the freshness caveat appended; no filler or redundancy.

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?

An output schema exists, so return values need no explanation, and annotations cover safety for this simple read tool. The remaining gap is minor: 'session' is undefined (pre-market, regular hours, or last close) and error behavior for unresolvable symbols is unstated.

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?

Only one parameter, but schema description coverage is 0%, so the description must compensate. It does restate the 1-50 bound (already encoded as minItems/maxItems) but says nothing about symbol format, exchange suffixes, or what happens with invalid or delisted symbols.

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 ('Get') and resource ('latest session quotes') plus the cardinality limit (1-50 symbols). It distinguishes itself from streaming price feeds, but does not differentiate from the closely related sibling get_market_snapshot or get_market_overview.

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?

The clause 'not real-time streaming prices' hints at when this is inappropriate but is not an explicit when-to-use rule, and no sibling alternative is named. An agent must infer from the sibling list whether it wants quotes or a snapshot.

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