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

Annotations already declare readOnlyHint=true and destructiveHint=false, and the description goes further with live-read-on-every-call, no paging, long answers on large databases, and even the exact refusal messages ('Insufficient rights', 'Connection not found'). That permission and error disclosure is genuinely useful, but return-shape and paging already carry the main behavioral weight for a read tool, so it sits at a solid mid-high rather than exceptional.

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 core verb and scope, then alternatives, then behavior, then permissions — a logical order with no filler. It runs long for a single-parameter read tool, but nearly every clause carries distinct information, so the density is justified.

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, yet the description spells out the return structure (schemas → tables → type and column names), plus the permission model, the exact error strings, and the no-paging characteristic. An agent can call this correctly and interpret the response without further exploration.

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 schema already explains that connectionId comes from fastero_list_connections or fastero_create_file_connection. The description adds only the adjacent fact that an uploaded file's connection holds one table, which is contextual rather than parameter-level; the schema does the heavy lifting, so baseline 3 applies.

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 — 'List the schemas, tables and columns that a connection's database login can see' — and pins the scope to what the login can see, which is the exact axis an agent needs. It is unmistakably distinct from sibling list tools like fastero_list_connections or fastero_get_connection.

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 routes usage: 'Use it to find table and column names before fastero_run_sql or fastero_create_query,' and then rules out the two nearest neighbours by stating what fastero_get_definitions and fastero_get_connection hold instead. When-to-use and when-not-to-use are both covered without inference.

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