Market overview and indices

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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, openWorld), so the description's added value is in output shape: 'The first block is the market overview' and the fact that each index carries an ins_code. It does not mention the 70-row cap behavior beyond the schema or result size, which keeps it off a 5.

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, then usage examples, then the sibling routing rule. Every sentence carries information; the trailing 'The first block is the market overview' is slightly stranded at the end rather than grouped with output expectations.

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?

No output schema exists, and the description does compensate by describing the response layout (market-overview block first, then ranked indices with ins_code). It could say more about what the ranking actually returns per index, but an agent has enough to call it and interpret the result.

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 enum values and defaults are fully documented in the schema, so this is the baseline case. The description reinforces the ranking concept ('by return') but adds no format or semantics the schema doesn't already carry.

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: 'Show the Tehran and Farabourse market summary and rank the 65 market and industry indices by return.' The scope (65 indices, ranked by return) plus the market summary distinguishes it cleanly from fp_index_history and fp_industries.

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 concrete trigger phrasings ('how is the bourse today', 'which industries are up this year', 'what is the total index') and an explicit handoff rule: pass the ins_code to fp_index_history for daily values. The boundary between this tool and its closest sibling is stated, not inferred.

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