read_query

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

No annotations provided, so description carries full burden. It discloses that the database is opened read-only (writes impossible), rejects multi-statement SQL and all DML/DDL/PRAGMA, and details the output structure with truncation semantics. This is a model of behavioral transparency for a tool with no annotations.

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?

The description is dense but perfectly organized: operation definition, supported features, prerequisite guidance, server rules, result format, and truncation handling. Every sentence adds critical information with no redundancy. Front-loads the core purpose and essential constraints, making it easy to parse.

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?

Covers everything an agent needs to call this tool correctly: allowed SQL types, supported clauses, schema discovery prerequisite, server-side restrictions, read-only guarantee, output format, truncation behavior, max_rows default, and remediation advice. With no output schema, the description provides a complete picture, making it highly complete for a complex SQL execution tool.

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 0%, so the description must add meaning. It explains the sql parameter implicitly (the SQL statement to execute) and mentions max_rows with its default and effect on truncation. While not a dedicated parameter-by-parameter breakdown, it effectively conveys the purpose and impact of both parameters, going well beyond the bare schema.

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?

The description states a specific verb (Execute), resource (read-only SQL statement against the shop database), and explicitly enumerates allowed SQL constructs (SELECT, WITH ... SELECT, JOIN, GROUP BY, etc.). This clearly distinguishes it from sibling tools list_tables and describe_table, which are schema introspection rather than data querying.

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?

Provides explicit when-to-use vs. alternatives: 'If you do not know the schema yet, call list_tables and describe_table first.' Also states constraints (one statement per call, no modification statements) and practical advice on handling truncation (refine query with LIMIT/WHERE/aggregation). This leaves no ambiguity about when and how to use the tool.

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