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

Beyond readOnlyHint/destructiveHint, it discloses what is deliberately excluded (no credentials, hosts, or test results), states the permission model ('Any member of the organisation can list them'), and explains the isSample flag so the agent will not mistake invented demo orders for real data.

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 purpose and consumer tools, then the returned fields, then exclusions and the sample-data caveat. It is a dense run-on paragraph and slightly overpacked, but nearly every clause carries information an agent needs.

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?

There is no output schema, and the description compensates by enumerating the returned fields (_id, name, datasource with its code values, database, creator, creation time). Combined with the access-model and sample-data notes, it is complete for a one-optional-param read 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 coverage is 100%, so the baseline is 3, but the description adds meaning: orgId may be omitted and can only ever be the organisation the key belongs to, so the agent knows the parameter is effectively non-selectable. It gives no format hints, but none are needed.

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 every data connection'), scopes it ('in this organisation, from all its projects'), and gives the reason for listing (to pick the connectionId consumed by fastero_run_sql, fastero_create_query, fastero_show_chart). It also clearly separates itself from fastero_get_connection and fastero_list_connection_schemas.

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?

Tells the agent when to call this (to obtain a connectionId for the run/query/chart tools) and when not to, naming the alternatives fastero_get_connection (settings and last test) and fastero_list_connection_schemas (tables). No inference is required.

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